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icon-filter"></span><span class="visually-hidden">Filter sidebar</span></label><input id="sidebar-filter-input" autoComplete="off" class="sidebar-filter-input-field false" type="text" placeholder="Filter" value=""/><button type="button" class="button action has-icon clear-sidebar-filter-button"><span class="button-wrap"><span class="icon icon-cancel "></span><span class="visually-hidden">Clear filter input</span></span></button></div></section></header><div class="sidebar-inner-nav"><div class="in-nav-toc"><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#built-ins">Built-ins</a></li><li class="document-toc-item "><a class="document-toc-link" href="#statements">Statements</a></li><li class="document-toc-item "><a class="document-toc-link" href="#expressions_and_operators">Expressions and operators</a></li><li class="document-toc-item "><a class="document-toc-link" href="#functions">Functions</a></li><li class="document-toc-item "><a class="document-toc-link" href="#classes">Classes</a></li><li class="document-toc-item "><a class="document-toc-link" href="#regular_expressions">Regular expressions</a></li><li class="document-toc-item "><a class="document-toc-link" href="#additional_reference_pages">Additional reference pages</a></li></ul></section></div></div><div class="sidebar-body"> <ol> <li class="section"><a href="/en-US/docs/Web/JavaScript">JavaScript</a></li> <li class="section">Tutorials</li> <li class="toggle"> <details> <summary>Complete beginners</summary> <ol> <li><a href="/en-US/docs/Learn/Getting_started_with_the_web/JavaScript_basics">JavaScript basics</a></li> <li><a href="/en-US/docs/Learn/JavaScript/First_steps">JavaScript first steps</a></li> <li><a href="/en-US/docs/Learn/JavaScript/Building_blocks">JavaScript building blocks</a></li> <li><a href="/en-US/docs/Learn/JavaScript/Objects">Introducing JavaScript objects</a></li> </ol> </details> </li> <li class="toggle"> <details> <summary>JavaScript Guide</summary> <ol> <li><a href="/en-US/docs/Web/JavaScript/Guide/Introduction">Introduction</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Grammar_and_types">Grammar and types</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling">Control flow and error handling</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration">Loops and iteration</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Functions">Functions</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Expressions_and_operators">Expressions and operators</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Numbers_and_dates">Numbers and dates</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Text_formatting">Text formatting</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Regular_expressions">Regular expressions</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Indexed_collections">Indexed collections</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Keyed_collections">Keyed collections</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Working_with_objects">Working with objects</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Using_classes">Using classes</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Using_promises">Using promises</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Typed_arrays">JavaScript typed arrays</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Iterators_and_generators">Iterators and generators</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Meta_programming">Meta programming</a></li> <li><a href="/en-US/docs/Web/JavaScript/Guide/Modules">JavaScript modules</a></li> </ol> </details> </li> <li class="toggle"> <details> <summary>Intermediate</summary> <ol> <li><a href="/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks">Client-side JavaScript frameworks</a></li> <li><a href="/en-US/docs/Learn/JavaScript/Client-side_web_APIs">Client-side web APIs</a></li> <li><a href="/en-US/docs/Web/JavaScript/Language_overview">Language overview</a></li> <li><a href="/en-US/docs/Web/JavaScript/Data_structures">JavaScript data structures</a></li> <li><a href="/en-US/docs/Web/JavaScript/Equality_comparisons_and_sameness">Equality comparisons and sameness</a></li> <li><a href="/en-US/docs/Web/JavaScript/Enumerability_and_ownership_of_properties">Enumerability and ownership of properties</a></li> <li><a href="/en-US/docs/Web/JavaScript/Closures">Closures</a></li> </ol> </details> </li> <li class="toggle"> <details> <summary>Advanced</summary> <ol> <li><a href="/en-US/docs/Web/JavaScript/Inheritance_and_the_prototype_chain">Inheritance and the prototype chain</a></li> <li><a href="/en-US/docs/Web/JavaScript/Memory_management">Memory Management</a></li> <li><a href="/en-US/docs/Web/JavaScript/Event_loop">Concurrency model and Event Loop</a></li> </ol> </details> </li> <li class="section"><em><a href="/en-US/docs/Web/JavaScript/Reference" aria-current="page">References</a></em></li> <li class="toggle"> <details> <summary>Built-in objects</summary> <ol><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects">Overview</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError">AggregateError</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array">Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer">ArrayBuffer</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncFunction">AsyncFunction</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGenerator">AsyncGenerator</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGeneratorFunction">AsyncGeneratorFunction</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncIterator">AsyncIterator</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Atomics">Atomics</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt">BigInt</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt64Array">BigInt64Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigUint64Array">BigUint64Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean">Boolean</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView">DataView</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date">Date</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURI">decodeURI()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURIComponent">decodeURIComponent()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURI">encodeURI()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent">encodeURIComponent()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error">Error</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/escape">escape()</a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval">eval()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/EvalError">EvalError</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/FinalizationRegistry">FinalizationRegistry</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float16Array">Float16Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float32Array">Float32Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float64Array">Float64Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function">Function</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Generator">Generator</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/GeneratorFunction">GeneratorFunction</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis">globalThis</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Infinity">Infinity</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int16Array">Int16Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int32Array">Int32Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int8Array">Int8Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/InternalError">InternalError</a><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl">Intl</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/isFinite">isFinite()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/isNaN">isNaN()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Iterator">Iterator</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON">JSON</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map">Map</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math">Math</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/NaN">NaN</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number">Number</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object">Object</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseFloat">parseFloat()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt">parseInt()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise">Promise</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy">Proxy</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/RangeError">RangeError</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/ReferenceError">ReferenceError</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect">Reflect</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp">RegExp</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set">Set</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/SharedArrayBuffer">SharedArrayBuffer</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/String">String</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol">Symbol</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/SyntaxError">SyntaxError</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray">TypedArray</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypeError">TypeError</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint16Array">Uint16Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint32Array">Uint32Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array">Uint8Array</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8ClampedArray">Uint8ClampedArray</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined">undefined</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/unescape">unescape()</a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/URIError">URIError</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap">WeakMap</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakRef">WeakRef</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet">WeakSet</a></li></ol> </details> </li> <li class="toggle"> <details> <summary>Expressions & operators</summary> <ol><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators">Overview</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Addition">Addition (+)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Addition_assignment">Addition assignment (+=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Assignment">Assignment (=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/async_function">async function expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/async_function*">async function* expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/await">await</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND">Bitwise AND (&)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND_assignment">Bitwise AND assignment (&=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_NOT">Bitwise NOT (~)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR">Bitwise OR (|)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR_assignment">Bitwise OR assignment (|=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR">Bitwise XOR (^)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR_assignment">Bitwise XOR assignment (^=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/class">class expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Comma_operator">Comma operator (,)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_operator">Conditional (ternary) operator</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Decrement">Decrement (--)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/delete">delete</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment">Destructuring assignment</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Division">Division (/)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Division_assignment">Division assignment (/=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Equality">Equality (==)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation">Exponentiation (**)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation_assignment">Exponentiation assignment (**=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/function">function expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/function*">function* expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than">Greater than (>)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than_or_equal">Greater than or equal (>=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Grouping">Grouping operator ( )</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/import.meta">import.meta</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/import">import()</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/in">in</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Increment">Increment (++)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Inequality">Inequality (!=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/instanceof">instanceof</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift">Left shift (<<)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift_assignment">Left shift assignment (<<=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Less_than">Less than (<)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Less_than_or_equal">Less than or equal (<=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND">Logical AND (&&)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND_assignment">Logical AND assignment (&&=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT">Logical NOT (!)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR">Logical OR (||)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR_assignment">Logical OR assignment (||=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication">Multiplication (*)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication_assignment">Multiplication assignment (*=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/new">new</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/new.target">new.target</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/null">null</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing_assignment">Nullish coalescing assignment (??=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing">Nullish coalescing operator (??)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Object_initializer">Object initializer</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Operator_precedence">Operator precedence</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining">Optional chaining (?.)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Property_accessors">Property accessors</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Remainder">Remainder (%)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Remainder_assignment">Remainder assignment (%=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift">Right shift (>>)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift_assignment">Right shift assignment (>>=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax">Spread syntax (...)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Strict_equality">Strict equality (===)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Strict_inequality">Strict inequality (!==)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction">Subtraction (-)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction_assignment">Subtraction assignment (-=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/super">super</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/this">this</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/typeof">typeof</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unary_negation">Unary negation (-)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unary_plus">Unary plus (+)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift">Unsigned right shift (>>>)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift_assignment">Unsigned right shift assignment (>>>=)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/void">void operator</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/yield">yield</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/yield*">yield*</a></li></ol> </details> </li> <li class="toggle"> <details> <summary>Statements & declarations</summary> <ol><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements">Overview</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/async_function">async function</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/async_function*">async function*</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/block">Block statement</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/break">break</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/class">class</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/const">const</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/continue">continue</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/debugger">debugger</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/do...while">do...while</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/Empty">Empty statement</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/export">export</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/Expression_statement">Expression statement</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for">for</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for-await...of">for await...of</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for...in">for...in</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for...of">for...of</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/function">function</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/function*">function*</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/if...else">if...else</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/import">import</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/label">Labeled statement</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/let">let</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/return">return</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/switch">switch</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/throw">throw</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/try...catch">try...catch</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/var">var</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/while">while</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/with">with</a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li></ol> </details> </li> <li class="toggle"> <details> <summary>Functions</summary> <ol><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions">Overview</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions">Arrow function expressions</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/Default_parameters">Default parameters</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/get">get</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/Method_definitions">Method definitions</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters">Rest parameters</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/set">set</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/arguments">The arguments object</a></li></ol> </details> </li> <li class="toggle"> <details> <summary>Classes</summary> <ol><li><a href="/en-US/docs/Web/JavaScript/Reference/Classes">Overview</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/constructor">constructor</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/extends">extends</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/Private_properties">Private properties</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/Public_class_fields">Public class fields</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/static">static</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/Static_initialization_blocks">Static initialization blocks</a></li></ol> </details> </li> <li class="toggle"> <details> <summary>Regular expressions</summary> <ol><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions">Overview</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Backreference">Backreference: \1, \2</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Capturing_group">Capturing group: (...)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class_escape">Character class escape: \d, \D, \w, \W, \s, \S</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class">Character class: [...], [^...]</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_escape">Character escape: \n, \u{...}</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Disjunction">Disjunction: |</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Input_boundary_assertion">Input boundary assertion: ^, $</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Literal_character">Literal character: a, b</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookahead_assertion">Lookahead assertion: (?=...), (?!...)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookbehind_assertion">Lookbehind assertion: (?<=...), (?<!...)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Modifier">Modifier: (?ims-ims:...)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_backreference">Named backreference: \k<name></a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_capturing_group">Named capturing group: (?<name>...)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Non-capturing_group">Non-capturing group: (?:...)</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Quantifier">Quantifier: *, +, ?, {n}, {n,}, {n,m}</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Unicode_character_class_escape">Unicode character class escape: \p{...}, \P{...}</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Wildcard">Wildcard: .</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Word_boundary_assertion">Word boundary assertion: \b, \B</a></li></ol> </details> </li> <li class="toggle"> <details> <summary>Errors</summary> <ol><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors">Overview</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Promise_any_all_rejected">AggregateError: No Promise in Promise.any was resolved</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Property_access_denied">Error: Permission denied to access property "x"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Too_much_recursion">InternalError: too much recursion</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Not_a_valid_code_point">RangeError: argument is not a valid code point</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/BigInt_division_by_zero">RangeError: BigInt division by zero</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/BigInt_negative_exponent">RangeError: BigInt negative exponent</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Form_must_be_one_of">RangeError: form must be one of 'NFC', 'NFD', 'NFKC', or 'NFKD'</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_array_length">RangeError: invalid array length</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_date">RangeError: invalid date</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Precision_range">RangeError: precision is out of range</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_radix">RangeError: radix must be an integer</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Resulting_string_too_large">RangeError: repeat count must be less than infinity</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Negative_repetition_count">RangeError: repeat count must be non-negative</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_be_converted_to_BigInt_because_it_isnt_an_integer">RangeError: x can't be converted to BigInt because it isn't an integer</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Not_defined">ReferenceError: "x" is not defined</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Undeclared_var">ReferenceError: assignment to undeclared variable "x"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_access_lexical_declaration_before_init">ReferenceError: can't access lexical declaration 'X' before initialization</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_caller_or_arguments_usage">ReferenceError: deprecated caller or arguments usage</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Super_not_called">ReferenceError: must call super constructor before using 'this' in derived class constructor</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Super_called_twice">ReferenceError: super() called twice in derived class constructor</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_strict_arguments_eval">SyntaxError: 'arguments'/'eval' can't be defined or assigned to in strict mode code</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_octal_literal">SyntaxError: "0"-prefixed octal literals are deprecated</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Strict_non_simple_params">SyntaxError: "use strict" not allowed in function with non-simple parameters</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Reserved_identifier">SyntaxError: "x" is a reserved identifier</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_backslash_at_end_of_pattern">SyntaxError: \ at end of pattern</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_for-of_initializer">SyntaxError: a declaration in the head of a for-of loop can't have an initializer</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Delete_in_strict_mode">SyntaxError: applying the 'delete' operator to an unqualified name is deprecated</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Arguments_not_allowed">SyntaxError: arguments is not valid in fields</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_await">SyntaxError: await is only valid in async functions, async generators and modules</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/await_yield_in_parameter">SyntaxError: await/yield expression can't be used in parameter</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_use_nullish_coalescing_unparenthesized">SyntaxError: cannot use `??` unparenthesized within `||` and `&&` expressions</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_character_class_escape_in_class_range">SyntaxError: character class escape cannot be used in class range in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_continue">SyntaxError: continue must be inside loop</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_duplicate_capture_group_name">SyntaxError: duplicate capture group name in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Duplicate_parameter">SyntaxError: duplicate formal argument x</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_for-in_initializer">SyntaxError: for-in loop head declarations may not have initializers</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Unnamed_function_statement">SyntaxError: function statement requires a name</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Function_label">SyntaxError: functions cannot be labelled</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Either_be_both_static_or_non-static">SyntaxError: getter and setter for private name #x should either be both static or non-static</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Getter_no_arguments">SyntaxError: getter functions must have no arguments</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Identifier_after_number">SyntaxError: identifier starts immediately after numeric literal</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Illegal_character">SyntaxError: illegal character</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/import_decl_module_top_level">SyntaxError: import declarations may only appear at top level of a module</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_incomplete_quantifier">SyntaxError: incomplete quantifier in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_assignment_left-hand_side">SyntaxError: invalid assignment left-hand side</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_BigInt_syntax">SyntaxError: invalid BigInt syntax</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_capture_group_name">SyntaxError: invalid capture group name in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_char_in_class">SyntaxError: invalid character in class in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_class_set_operation">SyntaxError: invalid class set operation in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_decimal_escape">SyntaxError: invalid decimal escape in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_identity_escape">SyntaxError: invalid identity escape in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_named_capture_reference">SyntaxError: invalid named capture reference in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_property_name">SyntaxError: invalid property name in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_range_in_character_class">SyntaxError: invalid range in character class</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_group">SyntaxError: invalid regexp group</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_regexp_flag">SyntaxError: invalid regular expression flag "x"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_unicode_escape">SyntaxError: invalid unicode escape in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/JSON_bad_parse">SyntaxError: JSON.parse: bad parsing</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Label_not_found">SyntaxError: label not found</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_colon_after_property_id">SyntaxError: missing : after property id</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_parenthesis_after_argument_list">SyntaxError: missing ) after argument list</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_parenthesis_after_condition">SyntaxError: missing ) after condition</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_bracket_after_list">SyntaxError: missing ] after element list</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_curly_after_function_body">SyntaxError: missing } after function body</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_curly_after_property_list">SyntaxError: missing } after property list</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_initializer_in_const">SyntaxError: missing = in const declaration</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_formal_parameter">SyntaxError: missing formal parameter</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Missing_name_after_dot_operator">SyntaxError: missing name after . operator</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/No_variable_name">SyntaxError: missing variable name</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_negated_char_class_with_strings">SyntaxError: negated character class with strings in regular expression</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_new_optional">SyntaxError: new keyword cannot be used with an optional chain</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_nothing_to_repeat">SyntaxError: nothing to repeat</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_numbers_out_of_order_in_quantifier">SyntaxError: numbers out of order in {} quantifier.</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_octal_escape_sequence">SyntaxError: octal escape sequences can't be used in untagged template literals or in strict mode code</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Parameter_after_rest_parameter">SyntaxError: parameter after rest parameter</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_delete_private_fields">SyntaxError: private fields can't be deleted</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Duplicate_proto">SyntaxError: property name __proto__ appears more than once in object literal</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Regex_raw_bracket">SyntaxError: raw bracket is not allowed in regular expression with unicode flag</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Redeclared_parameter">SyntaxError: redeclaration of formal parameter "x"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Undeclared_private_field_or_method">SyntaxError: reference to undeclared private field or method #x</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Rest_with_default">SyntaxError: rest parameter may not have a default</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_return">SyntaxError: return not in function</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Setter_one_argument">SyntaxError: setter functions must have one argument</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/String_literal_EOL">SyntaxError: string literal contains an unescaped line break</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_super_call">SyntaxError: super() is only valid in derived class constructors</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_optional_template">SyntaxError: tagged template cannot be used with optional chain</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Hash_outside_class">SyntaxError: Unexpected '#' used outside of class body</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Unexpected_token">SyntaxError: Unexpected token</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_break">SyntaxError: unlabeled break must be inside loop or switch</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Unparenthesized_unary_expr_lhs_exponentiation">SyntaxError: unparenthesized unary expression can't appear on the left-hand side of '**'</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Bad_super_prop">SyntaxError: use of super property/member accesses only valid within methods or eval code within methods</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_source_map_pragma">SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. Use //# instead</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/is_not_iterable">TypeError: 'x' is not iterable</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Unexpected_type">TypeError: "x" is (not) "y"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Not_a_constructor">TypeError: "x" is not a constructor</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Not_a_function">TypeError: "x" is not a function</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/No_non-null_object">TypeError: "x" is not a non-null object</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Read-only">TypeError: "x" is read-only</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/BigInt_not_serializable">TypeError: BigInt value can't be serialized in JSON</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Builtin_ctor_no_new">TypeError: calling a builtin X constructor without new is forbidden</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Get_set_missing_private">TypeError: can't access/set private field or method: object is not the right class</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_assign_to_property">TypeError: can't assign to property "x" on "y": not an object</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_convert_BigInt_to_number">TypeError: can't convert BigInt to number</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_convert_x_to_BigInt">TypeError: can't convert x to BigInt</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_define_property_object_not_extensible">TypeError: can't define property "x": "obj" is not extensible</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Non_configurable_array_element">TypeError: can't delete non-configurable array element</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_redefine_property">TypeError: can't redefine non-configurable property "x"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_set_prototype">TypeError: can't set prototype of this object</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cyclic_prototype">TypeError: can't set prototype: it would cause a prototype chain cycle</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/in_operator_no_object">TypeError: cannot use 'in' operator to search for 'x' in 'y'</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Class_ctor_no_new">TypeError: class constructors must be invoked with 'new'</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cyclic_object_value">TypeError: cyclic object value</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_derived_return">TypeError: derived class constructor returned invalid value x</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Private_setter_only">TypeError: getting private setter-only property</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Private_double_initialization">TypeError: Initializing an object twice is an error with private fields/methods</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/invalid_right_hand_side_instanceof_operand">TypeError: invalid 'instanceof' operand 'x'</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Array_sort_argument">TypeError: invalid Array.prototype.sort argument</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_const_assignment">TypeError: invalid assignment to const "x"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Constructor_cant_be_used_directly">TypeError: Iterator/AsyncIterator constructor can't be used directly</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Requires_global_RegExp">TypeError: matchAll/replaceAll must be called with a global RegExp</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/More_arguments_needed">TypeError: More arguments needed</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/No_properties">TypeError: null/undefined has no properties</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Cant_delete">TypeError: property "x" is non-configurable and can't be deleted</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Reduce_of_empty_array_with_no_initial_value">TypeError: Reduce of empty array with no initial value</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Getter_only">TypeError: setting getter-only property "x"</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Key_not_weakly_held">TypeError: WeakSet key/WeakMap value 'x' must be an object or an unregistered symbol</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Called_on_incompatible_type">TypeError: X.prototype.y called on incompatible type</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Malformed_URI">URIError: malformed URI sequence</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Already_has_pragma">Warning: -file- is being assigned a //# sourceMappingURL, but already has one</a></li><li><a href="/en-US/docs/Web/JavaScript/Reference/Errors/Stmt_after_return">Warning: unreachable code after return statement</a></li></ol> </details> </li> <li class="toggle"> <details> <summary>Misc</summary> <ol> <li><a href="/en-US/docs/Web/JavaScript/JavaScript_technologies_overview">JavaScript technologies overview</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Lexical_grammar">Lexical grammar</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Iteration_protocols">Iteration protocols</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Strict_mode">Strict mode</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Template_literals">Template literals</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Trailing_commas">Trailing commas</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Deprecated_and_obsolete_features">Deprecated features</a></li> </ol> </details> </li> </ol> </div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#built-ins">Built-ins</a></li><li class="document-toc-item "><a class="document-toc-link" href="#statements">Statements</a></li><li class="document-toc-item "><a class="document-toc-link" href="#expressions_and_operators">Expressions and operators</a></li><li class="document-toc-item "><a class="document-toc-link" href="#functions">Functions</a></li><li class="document-toc-item "><a class="document-toc-link" href="#classes">Classes</a></li><li class="document-toc-item "><a class="document-toc-link" href="#regular_expressions">Regular expressions</a></li><li class="document-toc-item "><a class="document-toc-link" href="#additional_reference_pages">Additional reference pages</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="en-US"><header><h1>JavaScript reference</h1></header><div class="section-content"><p>The JavaScript reference serves as a repository of facts about the JavaScript language. The entire language is described here in detail. As you write JavaScript code, you'll refer to these pages often (thus the title "JavaScript reference").</p> <p>The JavaScript language is intended to be used within some larger environment, be it a browser, server-side scripts, or similar. For the most part, this reference attempts to be environment-agnostic and does not target a web browser environment.</p> <p>If you are new to JavaScript, start with the <a href="/en-US/docs/Web/JavaScript/Guide">guide</a>. Once you have a firm grasp of the fundamentals, you can use the reference to get more details on individual objects and language constructs.</p></div><section aria-labelledby="built-ins"><h2 id="built-ins"><a href="#built-ins">Built-ins</a></h2><div class="section-content"><p><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects">JavaScript standard built-in objects</a>, along with their methods and properties.</p></div></section><section aria-labelledby="value_properties"><h3 id="value_properties"><a href="#value_properties">Value properties</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis"><code>globalThis</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Infinity"><code>Infinity</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/NaN"><code>NaN</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined"><code>undefined</code></a></li> </ul></div></section><section aria-labelledby="function_properties"><h3 id="function_properties"><a href="#function_properties">Function properties</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval"><code>eval()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/isFinite"><code>isFinite()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/isNaN"><code>isNaN()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseFloat"><code>parseFloat()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt"><code>parseInt()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURI"><code>decodeURI()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURIComponent"><code>decodeURIComponent()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURI"><code>encodeURI()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent"><code>encodeURIComponent()</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/escape"><code>escape()</code></a> <abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/unescape"><code>unescape()</code></a> <abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li> </ul></div></section><section aria-labelledby="fundamental_objects"><h3 id="fundamental_objects"><a href="#fundamental_objects">Fundamental objects</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object"><code>Object</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function"><code>Function</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean"><code>Boolean</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol"><code>Symbol</code></a></li> </ul></div></section><section aria-labelledby="error_objects"><h3 id="error_objects"><a href="#error_objects">Error objects</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error"><code>Error</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError"><code>AggregateError</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/EvalError"><code>EvalError</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/RangeError"><code>RangeError</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/ReferenceError"><code>ReferenceError</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/SyntaxError"><code>SyntaxError</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypeError"><code>TypeError</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/URIError"><code>URIError</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/InternalError"><code>InternalError</code></a> <abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li> </ul></div></section><section aria-labelledby="numbers_and_dates"><h3 id="numbers_and_dates"><a href="#numbers_and_dates">Numbers and dates</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number"><code>Number</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt"><code>BigInt</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math"><code>Math</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date"><code>Date</code></a></li> </ul></div></section><section aria-labelledby="text_processing"><h3 id="text_processing"><a href="#text_processing">Text processing</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/String"><code>String</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp"><code>RegExp</code></a></li> </ul></div></section><section aria-labelledby="indexed_collections"><h3 id="indexed_collections"><a href="#indexed_collections">Indexed collections</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array"><code>Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int8Array"><code>Int8Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array"><code>Uint8Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8ClampedArray"><code>Uint8ClampedArray</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int16Array"><code>Int16Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint16Array"><code>Uint16Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int32Array"><code>Int32Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint32Array"><code>Uint32Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt64Array"><code>BigInt64Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigUint64Array"><code>BigUint64Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float16Array"><code>Float16Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float32Array"><code>Float32Array</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float64Array"><code>Float64Array</code></a></li> </ul></div></section><section aria-labelledby="keyed_collections"><h3 id="keyed_collections"><a href="#keyed_collections">Keyed collections</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map"><code>Map</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set"><code>Set</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap"><code>WeakMap</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet"><code>WeakSet</code></a></li> </ul></div></section><section aria-labelledby="structured_data"><h3 id="structured_data"><a href="#structured_data">Structured data</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer"><code>ArrayBuffer</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/SharedArrayBuffer"><code>SharedArrayBuffer</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView"><code>DataView</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Atomics"><code>Atomics</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON"><code>JSON</code></a></li> </ul></div></section><section aria-labelledby="managing_memory"><h3 id="managing_memory"><a href="#managing_memory">Managing memory</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakRef"><code>WeakRef</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/FinalizationRegistry"><code>FinalizationRegistry</code></a></li> </ul></div></section><section aria-labelledby="control_abstraction_objects"><h3 id="control_abstraction_objects"><a href="#control_abstraction_objects">Control abstraction objects</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Iterator"><code>Iterator</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncIterator"><code>AsyncIterator</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise"><code>Promise</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/GeneratorFunction"><code>GeneratorFunction</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGeneratorFunction"><code>AsyncGeneratorFunction</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Generator"><code>Generator</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGenerator"><code>AsyncGenerator</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncFunction"><code>AsyncFunction</code></a></li> </ul></div></section><section aria-labelledby="reflection"><h3 id="reflection"><a href="#reflection">Reflection</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect"><code>Reflect</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy"><code>Proxy</code></a></li> </ul></div></section><section aria-labelledby="internationalization"><h3 id="internationalization"><a href="#internationalization">Internationalization</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl"><code>Intl</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Collator"><code>Intl.Collator</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat"><code>Intl.DateTimeFormat</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DisplayNames"><code>Intl.DisplayNames</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DurationFormat"><code>Intl.DurationFormat</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat"><code>Intl.ListFormat</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Locale"><code>Intl.Locale</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat"><code>Intl.NumberFormat</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/PluralRules"><code>Intl.PluralRules</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/RelativeTimeFormat"><code>Intl.RelativeTimeFormat</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Segmenter"><code>Intl.Segmenter</code></a></li> </ul></div></section><section aria-labelledby="statements"><h2 id="statements"><a href="#statements">Statements</a></h2><div class="section-content"><p><a href="/en-US/docs/Web/JavaScript/Reference/Statements">JavaScript statements and declarations</a></p></div></section><section aria-labelledby="control_flow"><h3 id="control_flow"><a href="#control_flow">Control flow</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/return"><code>return</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/break"><code>break</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/continue"><code>continue</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/throw"><code>throw</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/if...else"><code>if...else</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/switch"><code>switch</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/try...catch"><code>try...catch</code></a></li> </ul></div></section><section aria-labelledby="declaring_variables"><h3 id="declaring_variables"><a href="#declaring_variables">Declaring variables</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/var"><code>var</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/let"><code>let</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/const"><code>const</code></a></li> </ul></div></section><section aria-labelledby="functions_and_classes"><h3 id="functions_and_classes"><a href="#functions_and_classes">Functions and classes</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/function"><code>function</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/function*"><code>function*</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/async_function"><code>async function</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/async_function*"><code>async function*</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/class"><code>class</code></a></li> </ul></div></section><section aria-labelledby="iterations"><h3 id="iterations"><a href="#iterations">Iterations</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/do...while"><code>do...while</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for"><code>for</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for...in"><code>for...in</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for...of"><code>for...of</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/for-await...of"><code>for await...of</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/while"><code>while</code></a></li> </ul></div></section><section aria-labelledby="others"><h3 id="others"><a href="#others">Others</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/Empty">Empty</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/block">Block</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/Expression_statement">Expression statement</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/debugger"><code>debugger</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/export"><code>export</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/import"><code>import</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/label">label</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Statements/with"><code>with</code></a> <abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li> </ul></div></section><section aria-labelledby="expressions_and_operators"><h2 id="expressions_and_operators"><a href="#expressions_and_operators">Expressions and operators</a></h2><div class="section-content"><p><a href="/en-US/docs/Web/JavaScript/Reference/Operators">JavaScript expressions and operators</a>.</p></div></section><section aria-labelledby="primary_expressions"><h3 id="primary_expressions"><a href="#primary_expressions">Primary expressions</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/this"><code>this</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Lexical_grammar#literals">Literals</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array"><code>[]</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Object_initializer"><code>{}</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/function"><code>function</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/class"><code>class</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/function*"><code>function*</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/async_function"><code>async function</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/async_function*"><code>async function*</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp"><code>/ab+c/i</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Template_literals"><code>`string`</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Grouping"><code>( )</code></a></li> </ul></div></section><section aria-labelledby="left-hand-side_expressions"><h3 id="left-hand-side_expressions"><a href="#left-hand-side_expressions">Left-hand-side expressions</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Property_accessors">Property accessors</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining"><code>?.</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/new"><code>new</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/new.target"><code>new.target</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/import.meta"><code>import.meta</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/super"><code>super</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/import"><code>import()</code></a></li> </ul></div></section><section aria-labelledby="increment_and_decrement"><h3 id="increment_and_decrement"><a href="#increment_and_decrement">Increment and decrement</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Increment"><code>A++</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Decrement"><code>A--</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Increment"><code>++A</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Decrement"><code>--A</code></a></li> </ul></div></section><section aria-labelledby="unary_operators"><h3 id="unary_operators"><a href="#unary_operators">Unary operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/delete"><code>delete</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/void"><code>void</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/typeof"><code>typeof</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unary_plus"><code>+</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unary_negation"><code>-</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_NOT"><code>~</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT"><code>!</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/await"><code>await</code></a></li> </ul></div></section><section aria-labelledby="arithmetic_operators"><h3 id="arithmetic_operators"><a href="#arithmetic_operators">Arithmetic operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation"><code>**</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication"><code>*</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Division"><code>/</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Remainder"><code>%</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Addition"><code>+</code></a> (Plus)</li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction"><code>-</code></a></li> </ul></div></section><section aria-labelledby="relational_operators"><h3 id="relational_operators"><a href="#relational_operators">Relational operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Less_than"><code><</code></a> (Less than)</li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than"><code>></code></a> (Greater than)</li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Less_than_or_equal"><code><=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than_or_equal"><code>>=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/instanceof"><code>instanceof</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/in"><code>in</code></a></li> </ul></div></section><section aria-labelledby="equality_operators"><h3 id="equality_operators"><a href="#equality_operators">Equality operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Equality"><code>==</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Inequality"><code>!=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Strict_equality"><code>===</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Strict_inequality"><code>!==</code></a></li> </ul></div></section><section aria-labelledby="bitwise_shift_operators"><h3 id="bitwise_shift_operators"><a href="#bitwise_shift_operators">Bitwise shift operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift"><code><<</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift"><code>>></code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift"><code>>>></code></a></li> </ul></div></section><section aria-labelledby="binary_bitwise_operators"><h3 id="binary_bitwise_operators"><a href="#binary_bitwise_operators">Binary bitwise operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND"><code>&</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR"><code>|</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR"><code>^</code></a></li> </ul></div></section><section aria-labelledby="binary_logical_operators"><h3 id="binary_logical_operators"><a href="#binary_logical_operators">Binary logical operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND"><code>&&</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR"><code>||</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing"><code>??</code></a></li> </ul></div></section><section aria-labelledby="conditional_ternary_operator"><h3 id="conditional_ternary_operator"><a href="#conditional_ternary_operator">Conditional (ternary) operator</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_operator"><code>(condition ? ifTrue : ifFalse)</code></a></li> </ul></div></section><section aria-labelledby="assignment_operators"><h3 id="assignment_operators"><a href="#assignment_operators">Assignment operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Assignment"><code>=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication_assignment"><code>*=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Division_assignment"><code>/=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Remainder_assignment"><code>%=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Addition_assignment"><code>+=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction_assignment"><code>-=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift_assignment"><code><<=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift_assignment"><code>>>=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift_assignment"><code>>>>=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND_assignment"><code>&=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR_assignment"><code>^=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR_assignment"><code>|=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation_assignment"><code>**=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND_assignment"><code>&&=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR_assignment"><code>||=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing_assignment"><code>??=</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment"><code>[a, b] = arr</code>, <code>{ a, b } = obj</code></a></li> </ul></div></section><section aria-labelledby="yield_operators"><h3 id="yield_operators"><a href="#yield_operators">Yield operators</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/yield"><code>yield</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/yield*"><code>yield*</code></a></li> </ul></div></section><section aria-labelledby="spread_syntax"><h3 id="spread_syntax"><a href="#spread_syntax">Spread syntax</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax"><code>...obj</code></a></li> </ul></div></section><section aria-labelledby="comma_operator"><h3 id="comma_operator"><a href="#comma_operator">Comma operator</a></h3><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Comma_operator"><code>,</code></a></li> </ul></div></section><section aria-labelledby="functions"><h2 id="functions"><a href="#functions">Functions</a></h2><div class="section-content"><p><a href="/en-US/docs/Web/JavaScript/Reference/Functions">JavaScript functions.</a></p> <ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions">Arrow Functions</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/Default_parameters">Default parameters</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters">Rest parameters</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/arguments"><code>arguments</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/Method_definitions">Method definitions</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/get">getter</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Functions/set">setter</a></li> </ul></div></section><section aria-labelledby="classes"><h2 id="classes"><a href="#classes">Classes</a></h2><div class="section-content"><p><a href="/en-US/docs/Web/JavaScript/Reference/Classes">JavaScript classes.</a></p> <ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/constructor"><code>constructor</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/extends"><code>extends</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/Private_properties">Private properties</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/Public_class_fields">Public class fields</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/static"><code>static</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Classes/Static_initialization_blocks">Static initialization blocks</a></li> </ul></div></section><section aria-labelledby="regular_expressions"><h2 id="regular_expressions"><a href="#regular_expressions">Regular expressions</a></h2><div class="section-content"><p><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions">JavaScript regular expressions.</a></p> <ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Backreference">Backreference: <code>\1</code>, <code>\2</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Capturing_group">Capturing group: <code>(...)</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class">Character class: <code>[...]</code>, <code>[^...]</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class_escape">Character class escape: <code>\d</code>, <code>\D</code>, <code>\w</code>, <code>\W</code>, <code>\s</code>, <code>\S</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_escape">Character escape: <code>\n</code>, <code>\u{...}</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Disjunction">Disjunction: <code>|</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Input_boundary_assertion">Input boundary assertion: <code>^</code>, <code>$</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Literal_character">Literal character: <code>a</code>, <code>b</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookahead_assertion">Lookahead assertion: <code>(?=...)</code>, <code>(?!...)</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookbehind_assertion">Lookbehind assertion: <code>(?<=...)</code>, <code>(?<!...)</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Modifier">Modifier: <code>(?ims-ims:...)</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_backreference">Named backreference: <code>\k<name></code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_capturing_group">Named capturing group: <code>(?<name>...)</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Non-capturing_group">Non-capturing group: <code>(?:...)</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Quantifier">Quantifier: <code>*</code>, <code>+</code>, <code>?</code>, <code>{n}</code>, <code>{n,}</code>, <code>{n,m}</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Unicode_character_class_escape">Unicode character class escape: <code>\p{...}</code>, <code>\P{...}</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Wildcard">Wildcard: <code>.</code></a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Word_boundary_assertion">Word boundary assertion: <code>\b</code>, <code>\B</code></a></li> </ul></div></section><section aria-labelledby="additional_reference_pages"><h2 id="additional_reference_pages"><a href="#additional_reference_pages">Additional reference pages</a></h2><div class="section-content"><ul> <li><a href="/en-US/docs/Web/JavaScript/Reference/Lexical_grammar">Lexical grammar</a></li> <li><a href="/en-US/docs/Web/JavaScript/Data_structures">Data types and data structures</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Iteration_protocols">Iteration protocols</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Trailing_commas">Trailing commas</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Errors">Errors</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Strict_mode">Strict mode</a></li> <li><a href="/en-US/docs/Web/JavaScript/Reference/Deprecated_and_obsolete_features">Deprecated features</a></li> </ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg 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Content available under <a href="/en-US/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/en-US/docs/Web/JavaScript/Reference","doc":{"isMarkdown":true,"isTranslated":false,"isActive":true,"flaws":{},"title":"JavaScript reference","mdn_url":"/en-US/docs/Web/JavaScript/Reference","locale":"en-US","native":"English (US)","sidebarHTML":"\n <ol>\n <li class=\"section\"><a href=\"/en-US/docs/Web/JavaScript\">JavaScript</a></li>\n <li class=\"section\">Tutorials</li>\n <li class=\"toggle\">\n <details>\n <summary>Complete beginners</summary>\n <ol>\n <li><a href=\"/en-US/docs/Learn/Getting_started_with_the_web/JavaScript_basics\">JavaScript basics</a></li>\n <li><a href=\"/en-US/docs/Learn/JavaScript/First_steps\">JavaScript first steps</a></li>\n <li><a href=\"/en-US/docs/Learn/JavaScript/Building_blocks\">JavaScript building blocks</a></li>\n <li><a href=\"/en-US/docs/Learn/JavaScript/Objects\">Introducing JavaScript objects</a></li>\n </ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>JavaScript Guide</summary>\n <ol>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Introduction\">Introduction</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Grammar_and_types\">Grammar and types</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling\">Control flow and error handling</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration\">Loops and iteration</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Functions\">Functions</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Expressions_and_operators\">Expressions and operators</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Numbers_and_dates\">Numbers and dates</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Text_formatting\">Text formatting</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Regular_expressions\">Regular expressions</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Indexed_collections\">Indexed collections</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Keyed_collections\">Keyed collections</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Working_with_objects\">Working with objects</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Using_classes\">Using classes</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Using_promises\">Using promises</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Typed_arrays\">JavaScript typed arrays</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Iterators_and_generators\">Iterators and generators</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Meta_programming\">Meta programming</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Guide/Modules\">JavaScript modules</a></li>\n </ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Intermediate</summary>\n <ol>\n <li><a href=\"/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks\">Client-side JavaScript frameworks</a></li>\n <li><a href=\"/en-US/docs/Learn/JavaScript/Client-side_web_APIs\">Client-side web APIs</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Language_overview\">Language overview</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Data_structures\">JavaScript data structures</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Equality_comparisons_and_sameness\">Equality comparisons and sameness</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Enumerability_and_ownership_of_properties\">Enumerability and ownership of properties</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Closures\">Closures</a></li>\n </ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Advanced</summary>\n <ol>\n <li><a href=\"/en-US/docs/Web/JavaScript/Inheritance_and_the_prototype_chain\">Inheritance and the prototype chain</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Memory_management\">Memory Management</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Event_loop\">Concurrency model and Event Loop</a></li>\n </ol>\n </details>\n </li>\n <li class=\"section\"><em><a href=\"/en-US/docs/Web/JavaScript/Reference\" aria-current=\"page\">References</a></em></li>\n <li class=\"toggle\">\n <details>\n <summary>Built-in objects</summary>\n <ol><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects\">Overview</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError\">AggregateError</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array\">Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer\">ArrayBuffer</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncFunction\">AsyncFunction</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGenerator\">AsyncGenerator</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGeneratorFunction\">AsyncGeneratorFunction</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncIterator\">AsyncIterator</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Atomics\">Atomics</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt\">BigInt</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt64Array\">BigInt64Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigUint64Array\">BigUint64Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean\">Boolean</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView\">DataView</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date\">Date</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURI\">decodeURI()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURIComponent\">decodeURIComponent()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURI\">encodeURI()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent\">encodeURIComponent()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error\">Error</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/escape\">escape()</a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval\">eval()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/EvalError\">EvalError</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/FinalizationRegistry\">FinalizationRegistry</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float16Array\">Float16Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float32Array\">Float32Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float64Array\">Float64Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function\">Function</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Generator\">Generator</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/GeneratorFunction\">GeneratorFunction</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis\">globalThis</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Infinity\">Infinity</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int16Array\">Int16Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int32Array\">Int32Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int8Array\">Int8Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/InternalError\">InternalError</a><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl\">Intl</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/isFinite\">isFinite()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/isNaN\">isNaN()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Iterator\">Iterator</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON\">JSON</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map\">Map</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math\">Math</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/NaN\">NaN</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number\">Number</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object\">Object</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseFloat\">parseFloat()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt\">parseInt()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise\">Promise</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy\">Proxy</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/RangeError\">RangeError</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/ReferenceError\">ReferenceError</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect\">Reflect</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp\">RegExp</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set\">Set</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/SharedArrayBuffer\">SharedArrayBuffer</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/String\">String</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol\">Symbol</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/SyntaxError\">SyntaxError</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray\">TypedArray</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypeError\">TypeError</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint16Array\">Uint16Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint32Array\">Uint32Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array\">Uint8Array</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8ClampedArray\">Uint8ClampedArray</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined\">undefined</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/unescape\">unescape()</a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/URIError\">URIError</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap\">WeakMap</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakRef\">WeakRef</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet\">WeakSet</a></li></ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Expressions & operators</summary>\n <ol><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators\">Overview</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Addition\">Addition (+)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Addition_assignment\">Addition assignment (+=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Assignment\">Assignment (=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/async_function\">async function expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/async_function*\">async function* expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/await\">await</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND\">Bitwise AND (&)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND_assignment\">Bitwise AND assignment (&=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_NOT\">Bitwise NOT (~)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR\">Bitwise OR (|)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR_assignment\">Bitwise OR assignment (|=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR\">Bitwise XOR (^)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR_assignment\">Bitwise XOR assignment (^=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/class\">class expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Comma_operator\">Comma operator (,)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_operator\">Conditional (ternary) operator</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Decrement\">Decrement (--)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/delete\">delete</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment\">Destructuring assignment</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Division\">Division (/)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Division_assignment\">Division assignment (/=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Equality\">Equality (==)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation\">Exponentiation (**)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation_assignment\">Exponentiation assignment (**=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/function\">function expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/function*\">function* expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than\">Greater than (>)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than_or_equal\">Greater than or equal (>=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Grouping\">Grouping operator ( )</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/import.meta\">import.meta</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/import\">import()</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/in\">in</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Increment\">Increment (++)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Inequality\">Inequality (!=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/instanceof\">instanceof</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift\">Left shift (<<)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift_assignment\">Left shift assignment (<<=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Less_than\">Less than (<)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Less_than_or_equal\">Less than or equal (<=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND\">Logical AND (&&)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND_assignment\">Logical AND assignment (&&=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT\">Logical NOT (!)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR\">Logical OR (||)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR_assignment\">Logical OR assignment (||=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication\">Multiplication (*)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication_assignment\">Multiplication assignment (*=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/new\">new</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/new.target\">new.target</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/null\">null</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing_assignment\">Nullish coalescing assignment (??=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing\">Nullish coalescing operator (??)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Object_initializer\">Object initializer</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Operator_precedence\">Operator precedence</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining\">Optional chaining (?.)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Property_accessors\">Property accessors</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Remainder\">Remainder (%)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Remainder_assignment\">Remainder assignment (%=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift\">Right shift (>>)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift_assignment\">Right shift assignment (>>=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax\">Spread syntax (...)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Strict_equality\">Strict equality (===)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Strict_inequality\">Strict inequality (!==)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction\">Subtraction (-)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction_assignment\">Subtraction assignment (-=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/super\">super</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/this\">this</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/typeof\">typeof</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unary_negation\">Unary negation (-)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unary_plus\">Unary plus (+)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift\">Unsigned right shift (>>>)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift_assignment\">Unsigned right shift assignment (>>>=)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/void\">void operator</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/yield\">yield</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/yield*\">yield*</a></li></ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Statements & declarations</summary>\n <ol><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements\">Overview</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/async_function\">async function</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/async_function*\">async function*</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/block\">Block statement</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/break\">break</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/class\">class</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/const\">const</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/continue\">continue</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/debugger\">debugger</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/do...while\">do...while</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/Empty\">Empty statement</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/export\">export</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/Expression_statement\">Expression statement</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for\">for</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for-await...of\">for await...of</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for...in\">for...in</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for...of\">for...of</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/function\">function</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/function*\">function*</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/if...else\">if...else</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/import\">import</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/label\">Labeled statement</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/let\">let</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/return\">return</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/switch\">switch</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/throw\">throw</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/try...catch\">try...catch</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/var\">var</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/while\">while</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/with\">with</a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li></ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Functions</summary>\n <ol><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions\">Overview</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions\">Arrow function expressions</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/Default_parameters\">Default parameters</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/get\">get</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/Method_definitions\">Method definitions</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters\">Rest parameters</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/set\">set</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/arguments\">The arguments object</a></li></ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Classes</summary>\n <ol><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes\">Overview</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/constructor\">constructor</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/extends\">extends</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/Private_properties\">Private properties</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/Public_class_fields\">Public class fields</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/static\">static</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/Static_initialization_blocks\">Static initialization blocks</a></li></ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Regular expressions</summary>\n <ol><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions\">Overview</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Backreference\">Backreference: \\1, \\2</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Capturing_group\">Capturing group: (...)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class_escape\">Character class escape: \\d, \\D, \\w, \\W, \\s, \\S</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class\">Character class: [...], [^...]</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_escape\">Character escape: \\n, \\u{...}</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Disjunction\">Disjunction: |</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Input_boundary_assertion\">Input boundary assertion: ^, $</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Literal_character\">Literal character: a, b</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookahead_assertion\">Lookahead assertion: (?=...), (?!...)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookbehind_assertion\">Lookbehind assertion: (?<=...), (?<!...)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Modifier\">Modifier: (?ims-ims:...)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_backreference\">Named backreference: \\k<name></a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_capturing_group\">Named capturing group: (?<name>...)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Non-capturing_group\">Non-capturing group: (?:...)</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Quantifier\">Quantifier: *, +, ?, {n}, {n,}, {n,m}</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Unicode_character_class_escape\">Unicode character class escape: \\p{...}, \\P{...}</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Wildcard\">Wildcard: .</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Word_boundary_assertion\">Word boundary assertion: \\b, \\B</a></li></ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Errors</summary>\n <ol><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors\">Overview</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Promise_any_all_rejected\">AggregateError: No Promise in Promise.any was resolved</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Property_access_denied\">Error: Permission denied to access property \"x\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Too_much_recursion\">InternalError: too much recursion</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Not_a_valid_code_point\">RangeError: argument is not a valid code point</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/BigInt_division_by_zero\">RangeError: BigInt division by zero</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/BigInt_negative_exponent\">RangeError: BigInt negative exponent</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Form_must_be_one_of\">RangeError: form must be one of 'NFC', 'NFD', 'NFKC', or 'NFKD'</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_array_length\">RangeError: invalid array length</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_date\">RangeError: invalid date</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Precision_range\">RangeError: precision is out of range</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_radix\">RangeError: radix must be an integer</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Resulting_string_too_large\">RangeError: repeat count must be less than infinity</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Negative_repetition_count\">RangeError: repeat count must be non-negative</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_be_converted_to_BigInt_because_it_isnt_an_integer\">RangeError: x can't be converted to BigInt because it isn't an integer</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Not_defined\">ReferenceError: \"x\" is not defined</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Undeclared_var\">ReferenceError: assignment to undeclared variable \"x\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_access_lexical_declaration_before_init\">ReferenceError: can't access lexical declaration 'X' before initialization</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_caller_or_arguments_usage\">ReferenceError: deprecated caller or arguments usage</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Super_not_called\">ReferenceError: must call super constructor before using 'this' in derived class constructor</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Super_called_twice\">ReferenceError: super() called twice in derived class constructor</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_strict_arguments_eval\">SyntaxError: 'arguments'/'eval' can't be defined or assigned to in strict mode code</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_octal_literal\">SyntaxError: \"0\"-prefixed octal literals are deprecated</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Strict_non_simple_params\">SyntaxError: \"use strict\" not allowed in function with non-simple parameters</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Reserved_identifier\">SyntaxError: \"x\" is a reserved identifier</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_backslash_at_end_of_pattern\">SyntaxError: \\ at end of pattern</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_for-of_initializer\">SyntaxError: a declaration in the head of a for-of loop can't have an initializer</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Delete_in_strict_mode\">SyntaxError: applying the 'delete' operator to an unqualified name is deprecated</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Arguments_not_allowed\">SyntaxError: arguments is not valid in fields</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_await\">SyntaxError: await is only valid in async functions, async generators and modules</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/await_yield_in_parameter\">SyntaxError: await/yield expression can't be used in parameter</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_use_nullish_coalescing_unparenthesized\">SyntaxError: cannot use `??` unparenthesized within `||` and `&&` expressions</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_character_class_escape_in_class_range\">SyntaxError: character class escape cannot be used in class range in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_continue\">SyntaxError: continue must be inside loop</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_duplicate_capture_group_name\">SyntaxError: duplicate capture group name in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Duplicate_parameter\">SyntaxError: duplicate formal argument x</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_for-in_initializer\">SyntaxError: for-in loop head declarations may not have initializers</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Unnamed_function_statement\">SyntaxError: function statement requires a name</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Function_label\">SyntaxError: functions cannot be labelled</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Either_be_both_static_or_non-static\">SyntaxError: getter and setter for private name #x should either be both static or non-static</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Getter_no_arguments\">SyntaxError: getter functions must have no arguments</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Identifier_after_number\">SyntaxError: identifier starts immediately after numeric literal</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Illegal_character\">SyntaxError: illegal character</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/import_decl_module_top_level\">SyntaxError: import declarations may only appear at top level of a module</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_incomplete_quantifier\">SyntaxError: incomplete quantifier in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_assignment_left-hand_side\">SyntaxError: invalid assignment left-hand side</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_BigInt_syntax\">SyntaxError: invalid BigInt syntax</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_capture_group_name\">SyntaxError: invalid capture group name in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_char_in_class\">SyntaxError: invalid character in class in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_class_set_operation\">SyntaxError: invalid class set operation in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_decimal_escape\">SyntaxError: invalid decimal escape in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_identity_escape\">SyntaxError: invalid identity escape in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_named_capture_reference\">SyntaxError: invalid named capture reference in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_property_name\">SyntaxError: invalid property name in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_range_in_character_class\">SyntaxError: invalid range in character class</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_group\">SyntaxError: invalid regexp group</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_regexp_flag\">SyntaxError: invalid regular expression flag \"x\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_invalid_unicode_escape\">SyntaxError: invalid unicode escape in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/JSON_bad_parse\">SyntaxError: JSON.parse: bad parsing</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Label_not_found\">SyntaxError: label not found</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_colon_after_property_id\">SyntaxError: missing : after property id</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_parenthesis_after_argument_list\">SyntaxError: missing ) after argument list</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_parenthesis_after_condition\">SyntaxError: missing ) after condition</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_bracket_after_list\">SyntaxError: missing ] after element list</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_curly_after_function_body\">SyntaxError: missing } after function body</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_curly_after_property_list\">SyntaxError: missing } after property list</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_initializer_in_const\">SyntaxError: missing = in const declaration</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_formal_parameter\">SyntaxError: missing formal parameter</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Missing_name_after_dot_operator\">SyntaxError: missing name after . operator</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/No_variable_name\">SyntaxError: missing variable name</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_negated_char_class_with_strings\">SyntaxError: negated character class with strings in regular expression</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_new_optional\">SyntaxError: new keyword cannot be used with an optional chain</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_nothing_to_repeat\">SyntaxError: nothing to repeat</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_numbers_out_of_order_in_quantifier\">SyntaxError: numbers out of order in {} quantifier.</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_octal_escape_sequence\">SyntaxError: octal escape sequences can't be used in untagged template literals or in strict mode code</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Parameter_after_rest_parameter\">SyntaxError: parameter after rest parameter</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_delete_private_fields\">SyntaxError: private fields can't be deleted</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Duplicate_proto\">SyntaxError: property name __proto__ appears more than once in object literal</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Regex_raw_bracket\">SyntaxError: raw bracket is not allowed in regular expression with unicode flag</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Redeclared_parameter\">SyntaxError: redeclaration of formal parameter \"x\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Undeclared_private_field_or_method\">SyntaxError: reference to undeclared private field or method #x</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Rest_with_default\">SyntaxError: rest parameter may not have a default</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_return\">SyntaxError: return not in function</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Setter_one_argument\">SyntaxError: setter functions must have one argument</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/String_literal_EOL\">SyntaxError: string literal contains an unescaped line break</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_super_call\">SyntaxError: super() is only valid in derived class constructors</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_optional_template\">SyntaxError: tagged template cannot be used with optional chain</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Hash_outside_class\">SyntaxError: Unexpected '#' used outside of class body</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Unexpected_token\">SyntaxError: Unexpected token</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_break\">SyntaxError: unlabeled break must be inside loop or switch</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Unparenthesized_unary_expr_lhs_exponentiation\">SyntaxError: unparenthesized unary expression can't appear on the left-hand side of '**'</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Bad_super_prop\">SyntaxError: use of super property/member accesses only valid within methods or eval code within methods</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Deprecated_source_map_pragma\">SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. Use //# instead</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/is_not_iterable\">TypeError: 'x' is not iterable</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Unexpected_type\">TypeError: \"x\" is (not) \"y\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Not_a_constructor\">TypeError: \"x\" is not a constructor</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Not_a_function\">TypeError: \"x\" is not a function</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/No_non-null_object\">TypeError: \"x\" is not a non-null object</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Read-only\">TypeError: \"x\" is read-only</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/BigInt_not_serializable\">TypeError: BigInt value can't be serialized in JSON</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Builtin_ctor_no_new\">TypeError: calling a builtin X constructor without new is forbidden</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Get_set_missing_private\">TypeError: can't access/set private field or method: object is not the right class</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_assign_to_property\">TypeError: can't assign to property \"x\" on \"y\": not an object</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_convert_BigInt_to_number\">TypeError: can't convert BigInt to number</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_convert_x_to_BigInt\">TypeError: can't convert x to BigInt</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_define_property_object_not_extensible\">TypeError: can't define property \"x\": \"obj\" is not extensible</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Non_configurable_array_element\">TypeError: can't delete non-configurable array element</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_redefine_property\">TypeError: can't redefine non-configurable property \"x\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_set_prototype\">TypeError: can't set prototype of this object</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cyclic_prototype\">TypeError: can't set prototype: it would cause a prototype chain cycle</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/in_operator_no_object\">TypeError: cannot use 'in' operator to search for 'x' in 'y'</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Class_ctor_no_new\">TypeError: class constructors must be invoked with 'new'</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cyclic_object_value\">TypeError: cyclic object value</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_derived_return\">TypeError: derived class constructor returned invalid value x</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Private_setter_only\">TypeError: getting private setter-only property</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Private_double_initialization\">TypeError: Initializing an object twice is an error with private fields/methods</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/invalid_right_hand_side_instanceof_operand\">TypeError: invalid 'instanceof' operand 'x'</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Array_sort_argument\">TypeError: invalid Array.prototype.sort argument</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Invalid_const_assignment\">TypeError: invalid assignment to const \"x\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Constructor_cant_be_used_directly\">TypeError: Iterator/AsyncIterator constructor can't be used directly</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Requires_global_RegExp\">TypeError: matchAll/replaceAll must be called with a global RegExp</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/More_arguments_needed\">TypeError: More arguments needed</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/No_properties\">TypeError: null/undefined has no properties</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Cant_delete\">TypeError: property \"x\" is non-configurable and can't be deleted</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Reduce_of_empty_array_with_no_initial_value\">TypeError: Reduce of empty array with no initial value</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Getter_only\">TypeError: setting getter-only property \"x\"</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Key_not_weakly_held\">TypeError: WeakSet key/WeakMap value 'x' must be an object or an unregistered symbol</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Called_on_incompatible_type\">TypeError: X.prototype.y called on incompatible type</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Malformed_URI\">URIError: malformed URI sequence</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Already_has_pragma\">Warning: -file- is being assigned a //# sourceMappingURL, but already has one</a></li><li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors/Stmt_after_return\">Warning: unreachable code after return statement</a></li></ol>\n </details>\n </li>\n <li class=\"toggle\">\n <details>\n <summary>Misc</summary>\n <ol>\n <li><a href=\"/en-US/docs/Web/JavaScript/JavaScript_technologies_overview\">JavaScript technologies overview</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Lexical_grammar\">Lexical grammar</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Iteration_protocols\">Iteration protocols</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Strict_mode\">Strict mode</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Template_literals\">Template literals</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Trailing_commas\">Trailing commas</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Deprecated_and_obsolete_features\">Deprecated features</a></li>\n </ol>\n </details>\n </li>\n </ol>\n","sidebarMacro":"JsSidebar","body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>The JavaScript reference serves as a repository of facts about the JavaScript language. The entire language is described here in detail. As you write JavaScript code, you'll refer to these pages often (thus the title \"JavaScript reference\").</p>\n<p>The JavaScript language is intended to be used within some larger environment, be it a browser, server-side scripts, or similar. For the most part, this reference attempts to be environment-agnostic and does not target a web browser environment.</p>\n<p>If you are new to JavaScript, start with the <a href=\"/en-US/docs/Web/JavaScript/Guide\">guide</a>. Once you have a firm grasp of the fundamentals, you can use the reference to get more details on individual objects and language constructs.</p>"}},{"type":"prose","value":{"id":"built-ins","title":"Built-ins","isH3":false,"content":"<p><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects\">JavaScript standard built-in objects</a>, along with their methods and properties.</p>"}},{"type":"prose","value":{"id":"value_properties","title":"Value properties","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/globalThis\"><code>globalThis</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Infinity\"><code>Infinity</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/NaN\"><code>NaN</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/undefined\"><code>undefined</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"function_properties","title":"Function properties","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval\"><code>eval()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/isFinite\"><code>isFinite()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/isNaN\"><code>isNaN()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseFloat\"><code>parseFloat()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt\"><code>parseInt()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURI\"><code>decodeURI()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURIComponent\"><code>decodeURIComponent()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURI\"><code>encodeURI()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent\"><code>encodeURIComponent()</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/escape\"><code>escape()</code></a> <abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/unescape\"><code>unescape()</code></a> <abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li>\n</ul>"}},{"type":"prose","value":{"id":"fundamental_objects","title":"Fundamental objects","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object\"><code>Object</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function\"><code>Function</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean\"><code>Boolean</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol\"><code>Symbol</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"error_objects","title":"Error objects","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error\"><code>Error</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError\"><code>AggregateError</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/EvalError\"><code>EvalError</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/RangeError\"><code>RangeError</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/ReferenceError\"><code>ReferenceError</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/SyntaxError\"><code>SyntaxError</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypeError\"><code>TypeError</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/URIError\"><code>URIError</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/InternalError\"><code>InternalError</code></a> <abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n <span class=\"visually-hidden\">Non-standard</span>\n</abbr></li>\n</ul>"}},{"type":"prose","value":{"id":"numbers_and_dates","title":"Numbers and dates","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number\"><code>Number</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt\"><code>BigInt</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math\"><code>Math</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date\"><code>Date</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"text_processing","title":"Text processing","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/String\"><code>String</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp\"><code>RegExp</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"indexed_collections","title":"Indexed collections","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array\"><code>Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int8Array\"><code>Int8Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8Array\"><code>Uint8Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint8ClampedArray\"><code>Uint8ClampedArray</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int16Array\"><code>Int16Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint16Array\"><code>Uint16Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Int32Array\"><code>Int32Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Uint32Array\"><code>Uint32Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigInt64Array\"><code>BigInt64Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/BigUint64Array\"><code>BigUint64Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float16Array\"><code>Float16Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float32Array\"><code>Float32Array</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Float64Array\"><code>Float64Array</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"keyed_collections","title":"Keyed collections","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map\"><code>Map</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set\"><code>Set</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap\"><code>WeakMap</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet\"><code>WeakSet</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"structured_data","title":"Structured data","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer\"><code>ArrayBuffer</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/SharedArrayBuffer\"><code>SharedArrayBuffer</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/DataView\"><code>DataView</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Atomics\"><code>Atomics</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON\"><code>JSON</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"managing_memory","title":"Managing memory","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakRef\"><code>WeakRef</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/FinalizationRegistry\"><code>FinalizationRegistry</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"control_abstraction_objects","title":"Control abstraction objects","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Iterator\"><code>Iterator</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncIterator\"><code>AsyncIterator</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise\"><code>Promise</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/GeneratorFunction\"><code>GeneratorFunction</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGeneratorFunction\"><code>AsyncGeneratorFunction</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Generator\"><code>Generator</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncGenerator\"><code>AsyncGenerator</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/AsyncFunction\"><code>AsyncFunction</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"reflection","title":"Reflection","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect\"><code>Reflect</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy\"><code>Proxy</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"internationalization","title":"Internationalization","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl\"><code>Intl</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Collator\"><code>Intl.Collator</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat\"><code>Intl.DateTimeFormat</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DisplayNames\"><code>Intl.DisplayNames</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DurationFormat\"><code>Intl.DurationFormat</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/ListFormat\"><code>Intl.ListFormat</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Locale\"><code>Intl.Locale</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat\"><code>Intl.NumberFormat</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/PluralRules\"><code>Intl.PluralRules</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/RelativeTimeFormat\"><code>Intl.RelativeTimeFormat</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Segmenter\"><code>Intl.Segmenter</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"statements","title":"Statements","isH3":false,"content":"<p><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements\">JavaScript statements and declarations</a></p>"}},{"type":"prose","value":{"id":"control_flow","title":"Control flow","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/return\"><code>return</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/break\"><code>break</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/continue\"><code>continue</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/throw\"><code>throw</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/if...else\"><code>if...else</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/switch\"><code>switch</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/try...catch\"><code>try...catch</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"declaring_variables","title":"Declaring variables","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/var\"><code>var</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/let\"><code>let</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/const\"><code>const</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"functions_and_classes","title":"Functions and classes","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/function\"><code>function</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/function*\"><code>function*</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/async_function\"><code>async function</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/async_function*\"><code>async function*</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/class\"><code>class</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"iterations","title":"Iterations","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/do...while\"><code>do...while</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for\"><code>for</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for...in\"><code>for...in</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for...of\"><code>for...of</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/for-await...of\"><code>for await...of</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/while\"><code>while</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"others","title":"Others","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/Empty\">Empty</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/block\">Block</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/Expression_statement\">Expression statement</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/debugger\"><code>debugger</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/export\"><code>export</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/import\"><code>import</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/label\">label</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Statements/with\"><code>with</code></a> <abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n <span class=\"visually-hidden\">Deprecated</span>\n</abbr></li>\n</ul>"}},{"type":"prose","value":{"id":"expressions_and_operators","title":"Expressions and operators","isH3":false,"content":"<p><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators\">JavaScript expressions and operators</a>.</p>"}},{"type":"prose","value":{"id":"primary_expressions","title":"Primary expressions","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/this\"><code>this</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Lexical_grammar#literals\">Literals</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array\"><code>[]</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Object_initializer\"><code>{}</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/function\"><code>function</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/class\"><code>class</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/function*\"><code>function*</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/async_function\"><code>async function</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/async_function*\"><code>async function*</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp\"><code>/ab+c/i</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Template_literals\"><code>`string`</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Grouping\"><code>( )</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"left-hand-side_expressions","title":"Left-hand-side expressions","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Property_accessors\">Property accessors</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining\"><code>?.</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/new\"><code>new</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/new.target\"><code>new.target</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/import.meta\"><code>import.meta</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/super\"><code>super</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/import\"><code>import()</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"increment_and_decrement","title":"Increment and decrement","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Increment\"><code>A++</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Decrement\"><code>A--</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Increment\"><code>++A</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Decrement\"><code>--A</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"unary_operators","title":"Unary operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/delete\"><code>delete</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/void\"><code>void</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/typeof\"><code>typeof</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unary_plus\"><code>+</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unary_negation\"><code>-</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_NOT\"><code>~</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT\"><code>!</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/await\"><code>await</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"arithmetic_operators","title":"Arithmetic operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation\"><code>**</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication\"><code>*</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Division\"><code>/</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Remainder\"><code>%</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Addition\"><code>+</code></a> (Plus)</li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction\"><code>-</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"relational_operators","title":"Relational operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Less_than\"><code><</code></a> (Less than)</li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than\"><code>></code></a> (Greater than)</li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Less_than_or_equal\"><code><=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Greater_than_or_equal\"><code>>=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/instanceof\"><code>instanceof</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/in\"><code>in</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"equality_operators","title":"Equality operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Equality\"><code>==</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Inequality\"><code>!=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Strict_equality\"><code>===</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Strict_inequality\"><code>!==</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"bitwise_shift_operators","title":"Bitwise shift operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift\"><code><<</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift\"><code>>></code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift\"><code>>>></code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"binary_bitwise_operators","title":"Binary bitwise operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND\"><code>&</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR\"><code>|</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR\"><code>^</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"binary_logical_operators","title":"Binary logical operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND\"><code>&&</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR\"><code>||</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing\"><code>??</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"conditional_ternary_operator","title":"Conditional (ternary) operator","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_operator\"><code>(condition ? ifTrue : ifFalse)</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"assignment_operators","title":"Assignment operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Assignment\"><code>=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Multiplication_assignment\"><code>*=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Division_assignment\"><code>/=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Remainder_assignment\"><code>%=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Addition_assignment\"><code>+=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Subtraction_assignment\"><code>-=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Left_shift_assignment\"><code><<=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Right_shift_assignment\"><code>>>=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Unsigned_right_shift_assignment\"><code>>>>=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_AND_assignment\"><code>&=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_XOR_assignment\"><code>^=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR_assignment\"><code>|=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Exponentiation_assignment\"><code>**=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_AND_assignment\"><code>&&=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR_assignment\"><code>||=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing_assignment\"><code>??=</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment\"><code>[a, b] = arr</code>, <code>{ a, b } = obj</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"yield_operators","title":"Yield operators","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/yield\"><code>yield</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/yield*\"><code>yield*</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"spread_syntax","title":"Spread syntax","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax\"><code>...obj</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"comma_operator","title":"Comma operator","isH3":true,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Operators/Comma_operator\"><code>,</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"functions","title":"Functions","isH3":false,"content":"<p><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions\">JavaScript functions.</a></p>\n<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions\">Arrow Functions</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/Default_parameters\">Default parameters</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/rest_parameters\">Rest parameters</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/arguments\"><code>arguments</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/Method_definitions\">Method definitions</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/get\">getter</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Functions/set\">setter</a></li>\n</ul>"}},{"type":"prose","value":{"id":"classes","title":"Classes","isH3":false,"content":"<p><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes\">JavaScript classes.</a></p>\n<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/constructor\"><code>constructor</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/extends\"><code>extends</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/Private_properties\">Private properties</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/Public_class_fields\">Public class fields</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/static\"><code>static</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Classes/Static_initialization_blocks\">Static initialization blocks</a></li>\n</ul>"}},{"type":"prose","value":{"id":"regular_expressions","title":"Regular expressions","isH3":false,"content":"<p><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions\">JavaScript regular expressions.</a></p>\n<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Backreference\">Backreference: <code>\\1</code>, <code>\\2</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Capturing_group\">Capturing group: <code>(...)</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class\">Character class: <code>[...]</code>, <code>[^...]</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_class_escape\">Character class escape: <code>\\d</code>, <code>\\D</code>, <code>\\w</code>, <code>\\W</code>, <code>\\s</code>, <code>\\S</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Character_escape\">Character escape: <code>\\n</code>, <code>\\u{...}</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Disjunction\">Disjunction: <code>|</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Input_boundary_assertion\">Input boundary assertion: <code>^</code>, <code>$</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Literal_character\">Literal character: <code>a</code>, <code>b</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookahead_assertion\">Lookahead assertion: <code>(?=...)</code>, <code>(?!...)</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Lookbehind_assertion\">Lookbehind assertion: <code>(?<=...)</code>, <code>(?<!...)</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Modifier\">Modifier: <code>(?ims-ims:...)</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_backreference\">Named backreference: <code>\\k<name></code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Named_capturing_group\">Named capturing group: <code>(?<name>...)</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Non-capturing_group\">Non-capturing group: <code>(?:...)</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Quantifier\">Quantifier: <code>*</code>, <code>+</code>, <code>?</code>, <code>{n}</code>, <code>{n,}</code>, <code>{n,m}</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Unicode_character_class_escape\">Unicode character class escape: <code>\\p{...}</code>, <code>\\P{...}</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Wildcard\">Wildcard: <code>.</code></a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Regular_expressions/Word_boundary_assertion\">Word boundary assertion: <code>\\b</code>, <code>\\B</code></a></li>\n</ul>"}},{"type":"prose","value":{"id":"additional_reference_pages","title":"Additional reference pages","isH3":false,"content":"<ul>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Lexical_grammar\">Lexical grammar</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Data_structures\">Data types and data structures</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Iteration_protocols\">Iteration protocols</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Trailing_commas\">Trailing commas</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Errors\">Errors</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Strict_mode\">Strict mode</a></li>\n <li><a href=\"/en-US/docs/Web/JavaScript/Reference/Deprecated_and_obsolete_features\">Deprecated features</a></li>\n</ul>"}}],"toc":[{"text":"Built-ins","id":"built-ins"},{"text":"Statements","id":"statements"},{"text":"Expressions and operators","id":"expressions_and_operators"},{"text":"Functions","id":"functions"},{"text":"Classes","id":"classes"},{"text":"Regular expressions","id":"regular_expressions"},{"text":"Additional reference pages","id":"additional_reference_pages"}],"summary":"The JavaScript reference serves as a repository of facts about the JavaScript language. The entire language is described here in detail. As you write JavaScript code, you'll refer to these pages often (thus the title \"JavaScript reference\").","popularity":0.0929,"modified":"2024-11-05T16:29:23.000Z","other_translations":[{"locale":"de","title":"JavaScript-Referenz","native":"Deutsch"},{"locale":"es","title":"Referencia de JavaScript","native":"Español"},{"locale":"fr","title":"Référence JavaScript","native":"Français"},{"locale":"ja","title":"JavaScript リファレンス","native":"日本語"},{"locale":"ko","title":"JavaScript 참고서","native":"한국어"},{"locale":"pt-BR","title":"Referência JavaScript","native":"Português (do Brasil)"},{"locale":"ru","title":"Справочник по JavaScript","native":"Русский"},{"locale":"zh-CN","title":"JavaScript 参考","native":"中文 (简体)"},{"locale":"zh-TW","title":"JavaScript 參考文件","native":"正體中文 (繁體)"}],"pageType":"landing-page","source":{"folder":"en-us/web/javascript/reference","github_url":"https://github.com/mdn/content/blob/main/files/en-us/web/javascript/reference/index.md","last_commit_url":"https://github.com/mdn/content/commit/65c47ca4811ecd225b826e00fcf64f7d93043591","filename":"index.md"},"short_title":"Reference","parents":[{"uri":"/en-US/docs/Web","title":"References"},{"uri":"/en-US/docs/Web/JavaScript","title":"JavaScript"},{"uri":"/en-US/docs/Web/JavaScript/Reference","title":"Reference"}],"pageTitle":"JavaScript reference - JavaScript | MDN","noIndexing":false}}</script></body></html>