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<ul class="breadcrumbs"> <li><a href="https://www.python.org/" title="The Python Programming Language">Python</a> » </li> <li><a href="../pep-0000/">PEP Index</a> » </li> <li>PEP 764</li> </ul> <button id="colour-scheme-cycler" onClick="setColourScheme(nextColourScheme())"> <svg aria-hidden="true" class="colour-scheme-icon-when-auto"><use href="#svg-sun-half"></use></svg> <svg aria-hidden="true" class="colour-scheme-icon-when-dark"><use href="#svg-moon"></use></svg> <svg aria-hidden="true" class="colour-scheme-icon-when-light"><use href="#svg-sun"></use></svg> Toggle light / dark / auto colour theme </button> </header> <article> <section id="pep-content"> <h1 class="page-title">PEP 764 – Inlined typed dictionaries</h1> <dl class="rfc2822 field-list simple"> <dt class="field-odd">Author:</dt> <dd class="field-odd">Victorien Plot <contact at vctrn.dev></dd> <dt class="field-even">Sponsor:</dt> <dd class="field-even">Eric Traut <erictr at microsoft.com></dd> <dt class="field-odd">Discussions-To:</dt> <dd class="field-odd"><a class="reference external" href="https://discuss.python.org/t/78779">Discourse thread</a></dd> <dt class="field-even">Status:</dt> <dd class="field-even"><abbr title="Proposal under active discussion and revision">Draft</abbr></dd> <dt class="field-odd">Type:</dt> <dd class="field-odd"><abbr title="Normative PEP with a new feature for Python, implementation change for CPython or interoperability standard for the ecosystem">Standards Track</abbr></dd> <dt class="field-even">Topic:</dt> <dd class="field-even"><a class="reference external" href="../topic/typing/">Typing</a></dd> <dt class="field-odd">Created:</dt> <dd class="field-odd">25-Oct-2024</dd> <dt class="field-even">Python-Version:</dt> <dd class="field-even">3.14</dd> <dt class="field-odd">Post-History:</dt> <dd class="field-odd"><a class="reference external" href="https://discuss.python.org/t/78779" title="Discourse thread">29-Jan-2025</a></dd> </dl> <hr class="docutils" /> <section id="contents"> <details><summary>Table of Contents</summary><ul class="simple"> <li><a class="reference internal" href="#abstract">Abstract</a></li> <li><a class="reference internal" href="#motivation">Motivation</a></li> <li><a class="reference internal" href="#rationale">Rationale</a></li> <li><a class="reference internal" href="#specification">Specification</a><ul> <li><a class="reference internal" href="#typing-specification-changes">Typing specification changes</a></li> <li><a class="reference internal" href="#id1">Runtime behavior</a></li> </ul> </li> <li><a class="reference internal" href="#backwards-compatibility">Backwards Compatibility</a></li> <li><a class="reference internal" href="#security-implications">Security Implications</a></li> <li><a class="reference internal" href="#how-to-teach-this">How to Teach This</a></li> <li><a class="reference internal" href="#reference-implementation">Reference Implementation</a><ul> <li><a class="reference internal" href="#runtime-implementation">Runtime implementation</a></li> </ul> </li> <li><a class="reference internal" href="#rejected-ideas">Rejected Ideas</a><ul> <li><a class="reference internal" href="#using-the-functional-syntax-in-annotations">Using the functional syntax in annotations</a></li> <li><a class="reference internal" href="#using-dict-or-typing-dict-with-a-single-type-argument">Using <code class="docutils literal notranslate">dict</code> or <code class="docutils literal notranslate">typing.Dict</code> with a single type argument</a></li> <li><a class="reference internal" href="#using-a-simple-dictionary">Using a simple dictionary</a></li> <li><a class="reference internal" href="#extending-other-typed-dictionaries">Extending other typed dictionaries</a></li> </ul> </li> <li><a class="reference internal" href="#open-issues">Open Issues</a><ul> <li><a class="reference internal" href="#should-inlined-typed-dictionaries-be-proper-classes">Should inlined typed dictionaries be proper classes?</a></li> <li><a class="reference internal" href="#inlined-typed-dictionaries-and-extra-items">Inlined typed dictionaries and extra items</a></li> </ul> </li> <li><a class="reference internal" href="#copyright">Copyright</a></li> </ul> </details></section> <section id="abstract"> <h2><a class="toc-backref" href="#abstract" role="doc-backlink">Abstract</a></h2> <a class="pep reference internal" href="../pep-0589/" title="PEP 589 – TypedDict: Type Hints for Dictionaries with a Fixed Set of Keys">PEP 589</a> defines a <a class="reference external" href="https://typing.python.org/en/latest/spec/typeddict.html#typeddict-class-based-syntax" title="(in typing)">class-based</a> and a <a class="reference external" href="https://typing.python.org/en/latest/spec/typeddict.html#typeddict-functional-syntax" title="(in typing)">functional syntax</a> to create typed dictionaries. In both scenarios, it requires defining a class or assigning to a value. In some situations, this can add unnecessary boilerplate, especially if the typed dictionary is only used once. This PEP proposes the addition of a new inlined syntax, by subscripting the <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">TypedDict</code></a> type: <div class="highlight-default notranslate"><div class="highlight"><pre>from typing import TypedDict def get_movie() -> TypedDict[{'name': str, 'year': int}]: return { 'name': 'Blade Runner', 'year': 1982, } </pre></div> </div> </section> <section id="motivation"> <h2><a class="toc-backref" href="#motivation" role="doc-backlink">Motivation</a></h2> Python dictionaries are an essential data structure of the language. Many times, it is used to return or accept structured data in functions. However, it can get tedious to define <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">TypedDict</code></a> classes: <ul class="simple"> <li>A typed dictionary requires a name, which might not be relevant.</li> <li>Nested dictionaries require more than one class definition.</li> </ul> Taking a simple function returning some nested structured data as an example: <div class="highlight-default notranslate"><div class="highlight"><pre>from typing import TypedDict class ProductionCompany(TypedDict): name: str location: str class Movie(TypedDict): name: str year: int production: ProductionCompany def get_movie() -> Movie: return { 'name': 'Blade Runner', 'year': 1982, 'production': { 'name': 'Warner Bros.', 'location': 'California', } } </pre></div> </div> </section> <section id="rationale"> <h2><a class="toc-backref" href="#rationale" role="doc-backlink">Rationale</a></h2> The new inlined syntax can be used to resolve these problems: <div class="highlight-default notranslate"><div class="highlight"><pre>def get_movie() -> TypedDict[{'name': str, 'year': int, 'production': TypedDict[{'name': str, 'location': str}]}]: ... </pre></div> </div> While less useful (as the functional or even the class-based syntax can be used), inlined typed dictionaries can be assigned to a variable, as an alias: <div class="highlight-default notranslate"><div class="highlight"><pre>InlinedTD = TypedDict[{'name': str}] def get_movie() -> InlinedTD: ... </pre></div> </div> </section> <section id="specification"> <h2><a class="toc-backref" href="#specification" role="doc-backlink">Specification</a></h2> The <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">TypedDict</code></a> special form is made subscriptable, and accepts a single type argument which must be a <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">dict</code></a>, following the same semantics as the <a class="reference external" href="https://typing.python.org/en/latest/spec/typeddict.html#typeddict-functional-syntax" title="(in typing)">functional syntax</a> (the dictionary keys are strings representing the field names, and values are valid <a class="reference external" href="https://typing.python.org/en/latest/spec/annotations.html#annotation-expression" title="(in typing)">annotation expressions</a>). Only the comma-separated list of <code class="docutils literal notranslate">key: value</code> pairs within braces constructor (<code class="docutils literal notranslate">{k: <type>}</code>) is allowed, and should be specified directly as the type argument (i.e. it is not allowed to use a variable which was previously assigned a <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">dict</code></a> instance). Inlined typed dictionaries can be referred to as anonymous, meaning they don’t have a specific name (see the <a class="reference external" href="Runtimebehavior">runtime behavior</a> section). It is possible to define a nested inlined dictionary: <div class="highlight-default notranslate"><div class="highlight"><pre>Movie = TypedDict[{'name': str, 'production': TypedDict[{'location': str}]}] # Note that the following is invalid as per the updated `type_expression` grammar: Movie = TypedDict[{'name': str, 'production': {'location': str}}] </pre></div> </div> Although it is not possible to specify any class arguments such as <code class="docutils literal notranslate">total</code>, any <a class="reference external" href="https://typing.python.org/en/latest/spec/glossary.html#term-type-qualifier" title="(in typing)">type qualifier</a> can be used for individual fields: <div class="highlight-default notranslate"><div class="highlight"><pre>Movie = TypedDict[{'name': NotRequired[str], 'year': ReadOnly[int]}] </pre></div> </div> Inlined typed dictionaries are implicitly total, meaning all keys must be present. Using the <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.Required" title="(in Python v3.13)"><code class="xref py py-data docutils literal notranslate">Required</code></a> type qualifier is thus redundant. Type variables are allowed in inlined typed dictionaries, provided that they are bound to some outer scope: <div class="highlight-default notranslate"><div class="highlight"><pre>class C[T]: inlined_td: TypedDict[{'name': T}] # OK, `T` is scoped to the class `C`. reveal_type(C[int]().inlined_td['name']) # Revealed type is 'int' def fn[T](arg: T) -> TypedDict[{'name': T}]: ... # OK: `T` is scoped to the function `fn`. reveal_type(fn('a')['name']) # Revealed type is 'str' type InlinedTD[T] = TypedDict[{'name': T}] # OK, `T` is scoped to the type alias. T = TypeVar('T') InlinedTD = TypedDict[{'name': T}] # OK, same as the previous type alias, but using the old-style syntax. def func(): InlinedTD = TypedDict[{'name': T}] # Not OK: `T` refers to a type variable that is not bound to the scope of `func`. </pre></div> </div> <section id="typing-specification-changes"> <h3><a class="toc-backref" href="#typing-specification-changes" role="doc-backlink">Typing specification changes</a></h3> The inlined typed dictionary adds a new kind of <a class="reference external" href="https://typing.python.org/en/latest/spec/glossary.html#term-type-expression" title="(in typing)">type expression</a>. As such, the <a class="reference external" href="https://typing.python.org/en/latest/spec/annotations.html#grammar-token-expression-grammar-type_expression" title="(in typing)"><code class="xref std std-token docutils literal notranslate">type_expression</code></a> production will be updated to include the inlined syntax: <pre> new-type_expression ::= <a class="reference external" href="https://typing.python.org/en/latest/spec/annotations.html#grammar-token-expression-grammar-type_expression" title="(in typing)"><code class="xref docutils literal notranslate">type_expression</code></a> | <TypedDict> '[' '{' (string: ':' <a class="reference external" href="https://typing.python.org/en/latest/spec/annotations.html#grammar-token-expression-grammar-annotation_expression" title="(in typing)"><code class="xref docutils literal notranslate">annotation_expression</code></a> ',')* '}' ']' (where string is any string literal) </pre> </section> <section id="id1"> <h3><a class="toc-backref" href="#id1" role="doc-backlink">Runtime behavior</a></h3> Although <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">TypedDict</code></a> is commonly referred as a class, it is implemented as a function at runtime. To be made subscriptable, it will be changed to be a class. Creating an inlined typed dictionary results in a new class, so <code class="docutils literal notranslate">T1</code> and <code class="docutils literal notranslate">T2</code> are of the same type: <div class="highlight-default notranslate"><div class="highlight"><pre>from typing import TypedDict T1 = TypedDict('T1', {'a': int}) T2 = TypedDict[{'a': int}] </pre></div> </div> As inlined typed dictionaries are are meant to be anonymous, their <a class="reference external" href="https://docs.python.org/3/reference/datamodel.html#type.__name__" title="(in Python v3.13)"><code class="xref py py-attr docutils literal notranslate">__name__</code></a> attribute will be set to an empty string. </section> </section> <section id="backwards-compatibility"> <h2><a class="toc-backref" href="#backwards-compatibility" role="doc-backlink">Backwards Compatibility</a></h2> This PEP does not bring any backwards incompatible changes. </section> <section id="security-implications"> <h2><a class="toc-backref" href="#security-implications" role="doc-backlink">Security Implications</a></h2> There are no known security consequences arising from this PEP. </section> <section id="how-to-teach-this"> <h2><a class="toc-backref" href="#how-to-teach-this" role="doc-backlink">How to Teach This</a></h2> The new inlined syntax will be documented both in the <a class="reference external" href="https://docs.python.org/3/library/typing.html#module-typing" title="(in Python v3.13)"><code class="xref py py-mod docutils literal notranslate">typing</code></a> module documentation and the <a class="reference external" href="https://typing.python.org/en/latest/spec/typeddict.html#typed-dictionaries" title="(in typing)">typing specification</a>. When complex dictionary structures are used, having everything defined on a single line can hurt readability. Code formatters can help by formatting the inlined typed dictionary across multiple lines: <div class="highlight-default notranslate"><div class="highlight"><pre>def edit_movie( movie: TypedDict[{ 'name': str, 'year': int, 'production': TypedDict[{ 'location': str, }], }], ) -> None: ... </pre></div> </div> </section> <section id="reference-implementation"> <h2><a class="toc-backref" href="#reference-implementation" role="doc-backlink">Reference Implementation</a></h2> Mypy supports a similar syntax as an <a class="reference external" href="https://mypy.readthedocs.io/en/latest/command_line.html#cmdoption-mypy-enable-incomplete-feature" title="(in mypy v1.16.0+dev.f6295899f4bcda61dc4017fabdb9c85c844bcc53)"><code class="xref std std-option docutils literal notranslate">experimental feature</code></a>: <div class="highlight-default notranslate"><div class="highlight"><pre>def test_values() -> {"int": int, "str": str}: return {"int": 42, "str": "test"} </pre></div> </div> Pyright added support for the new syntax in version <a class="reference external" href="https://github.com/microsoft/pyright/releases/tag/1.1.387">1.1.387</a>. <section id="runtime-implementation"> <h3><a class="toc-backref" href="#runtime-implementation" role="doc-backlink">Runtime implementation</a></h3> A draft implementation is available <a class="reference external" href="https://github.com/Viicos/cpython/commit/49e5a83f">here</a>. </section> </section> <section id="rejected-ideas"> <h2><a class="toc-backref" href="#rejected-ideas" role="doc-backlink">Rejected Ideas</a></h2> <section id="using-the-functional-syntax-in-annotations"> <h3><a class="toc-backref" href="#using-the-functional-syntax-in-annotations" role="doc-backlink">Using the functional syntax in annotations</a></h3> The alternative functional syntax could be used as an annotation directly: <div class="highlight-default notranslate"><div class="highlight"><pre>def get_movie() -> TypedDict('Movie', {'title': str}): ... </pre></div> </div> However, call expressions are currently unsupported in such a context for various reasons (expensive to process, evaluating them is not standardized). This would also require a name which is sometimes not relevant. </section> <section id="using-dict-or-typing-dict-with-a-single-type-argument"> <h3><a class="toc-backref" href="#using-dict-or-typing-dict-with-a-single-type-argument" role="doc-backlink">Using <code class="docutils literal notranslate">dict</code> or <code class="docutils literal notranslate">typing.Dict</code> with a single type argument</a></h3> We could reuse <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">dict</code></a> or <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.Dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">typing.Dict</code></a> with a single type argument to express the same concept: <div class="highlight-default notranslate"><div class="highlight"><pre>def get_movie() -> dict[{'title': str}]: ... </pre></div> </div> While this would avoid having to import <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">TypedDict</code></a> from <a class="reference external" href="https://docs.python.org/3/library/typing.html#module-typing" title="(in Python v3.13)"><code class="xref py py-mod docutils literal notranslate">typing</code></a>, this solution has several downsides: <ul class="simple"> <li>For type checkers, <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">dict</code></a> is a regular class with two type variables. Allowing <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">dict</code></a> to be parametrized with a single type argument would require special casing from type checkers, as there is no way to express parametrization overloads. On the other hand, <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">TypedDict</code></a> is already a <a class="reference external" href="https://typing.python.org/en/latest/spec/glossary.html#term-special-form" title="(in typing)">special form</a>.</li> <li>If future work extends what inlined typed dictionaries can do, we don’t have to worry about impact of sharing the symbol with <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">dict</code></a>.</li> <li><a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.Dict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">typing.Dict</code></a> has been deprecated (although not planned for removal) by <a class="pep reference internal" href="../pep-0585/" title="PEP 585 – Type Hinting Generics In Standard Collections">PEP 585</a>. Having it used for a new typing feature would be confusing for users (and would require changes in code linters).</li> </ul> </section> <section id="using-a-simple-dictionary"> <h3><a class="toc-backref" href="#using-a-simple-dictionary" role="doc-backlink">Using a simple dictionary</a></h3> Instead of subscripting the <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict" title="(in Python v3.13)"><code class="xref py py-class docutils literal notranslate">TypedDict</code></a> class, a plain dictionary could be used as an annotation: <div class="highlight-default notranslate"><div class="highlight"><pre>def get_movie() -> {'title': str}: ... </pre></div> </div> However, <a class="pep reference internal" href="../pep-0584/" title="PEP 584 – Add Union Operators To dict">PEP 584</a> added union operators on dictionaries and <a class="pep reference internal" href="../pep-0604/" title="PEP 604 – Allow writing union types as X | Y">PEP 604</a> introduced <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#types-union" title="(in Python v3.13)">union types</a>. Both features make use of the <a class="reference external" href="https://docs.python.org/3/reference/expressions.html#bitwise" title="(in Python v3.13)">bitwise or (|)</a> operator, making the following use cases incompatible, especially for runtime introspection: <div class="highlight-default notranslate"><div class="highlight"><pre># Dictionaries are merged: def fn() -> {'a': int} | {'b': str}: ... # Raises a type error at runtime: def fn() -> {'a': int} | int: ... </pre></div> </div> </section> <section id="extending-other-typed-dictionaries"> <h3><a class="toc-backref" href="#extending-other-typed-dictionaries" role="doc-backlink">Extending other typed dictionaries</a></h3> Several syntaxes could be used to have the ability to extend other typed dictionaries: <div class="highlight-default notranslate"><div class="highlight"><pre>InlinedBase = TypedDict[{'a': int}] Inlined = TypedDict[InlinedBase, {'b': int}] # or, by providing a slice: Inlined = TypedDict[{'b': int} : (InlinedBase,)] </pre></div> </div> As inlined typed dictionaries are meant to only support a subset of the existing syntax, adding this extension mechanism isn’t compelling enough to be supported, considering the added complexity. If intersections were to be added into the type system, it could cover this use case. </section> </section> <section id="open-issues"> <h2><a class="toc-backref" href="#open-issues" role="doc-backlink">Open Issues</a></h2> <section id="should-inlined-typed-dictionaries-be-proper-classes"> <h3><a class="toc-backref" href="#should-inlined-typed-dictionaries-be-proper-classes" role="doc-backlink">Should inlined typed dictionaries be proper classes?</a></h3> The PEP currently defines inlined typed dictionaries as type objects, to be in line with the existing syntaxes. To work around the fact that they don’t have a name, their <a class="reference external" href="https://docs.python.org/3/reference/datamodel.html#type.__name__" title="(in Python v3.13)"><code class="xref py py-attr docutils literal notranslate">__name__</code></a> attribute is set to an empty string. This is somewhat arbitrary, and an alternative name could be used as well (e.g. <code class="docutils literal notranslate">'<TypedDict>'</code>). Alternatively, inlined typed dictionaries could be defined as instances of a new (internal) typing class, e.g. <code class="xref py py-class docutils literal notranslate">typing._InlinedTypedDict</code>. While this solves the naming issue, it requires extra logic in the runtime implementation to provide the introspection attributes (such as <a class="reference external" href="https://docs.python.org/3/library/typing.html#typing.TypedDict.__total__" title="(in Python v3.13)"><code class="xref py py-attr docutils literal notranslate">__total__</code></a>), and tools relying on runtime introspection would have to add proper support for this new type. Depending on the outcome of the runtime implementation, we can more or less easily allow extending inlined typed dictionaries: <div class="highlight-default notranslate"><div class="highlight"><pre>InlinedTD = TypedDict[{'a': int}] # If `InlinedTD` is a typing._InlinedTypedDict instance, this adds complexity: class SubTD(InlinedTD): pass </pre></div> </div> </section> <section id="inlined-typed-dictionaries-and-extra-items"> <h3><a class="toc-backref" href="#inlined-typed-dictionaries-and-extra-items" role="doc-backlink">Inlined typed dictionaries and extra items</a></h3> <a class="pep reference internal" href="../pep-0728/" title="PEP 728 – TypedDict with Typed Extra Items">PEP 728</a> introduces the concept of <a class="reference internal" href="../pep-0728/#typed-dict-closed">closed</a> type dictionaries. If this PEP were to be accepted, inlined typed dictionaries will be closed by default. This means <a class="pep reference internal" href="../pep-0728/" title="PEP 728 – TypedDict with Typed Extra Items">PEP 728</a> needs to be addressed first, so that this PEP can be updated accordingly. </section> </section> <section id="copyright"> <h2><a class="toc-backref" href="#copyright" role="doc-backlink">Copyright</a></h2> This document is placed in the public domain or under the CC0-1.0-Universal license, whichever is more permissive. </section> </section> <hr class="docutils" /> Source: <a class="reference external" href="https://github.com/python/peps/blob/main/peps/pep-0764.rst">https://github.com/python/peps/blob/main/peps/pep-0764.rst</a> Last modified: <a class="reference external" href="https://github.com/python/peps/commits/main/peps/pep-0764.rst">2025-03-04 15:00:34 GMT</a> </article> <nav id="pep-sidebar"> <h2>Contents</h2> <ul> <li><a class="reference internal" href="#abstract">Abstract</a></li> <li><a class="reference internal" href="#motivation">Motivation</a></li> <li><a class="reference internal" href="#rationale">Rationale</a></li> <li><a class="reference internal" href="#specification">Specification</a><ul> <li><a class="reference internal" href="#typing-specification-changes">Typing specification changes</a></li> <li><a class="reference internal" href="#id1">Runtime behavior</a></li> </ul> </li> <li><a class="reference internal" href="#backwards-compatibility">Backwards Compatibility</a></li> <li><a class="reference internal" href="#security-implications">Security Implications</a></li> <li><a class="reference internal" href="#how-to-teach-this">How to Teach This</a></li> <li><a class="reference internal" href="#reference-implementation">Reference Implementation</a><ul> <li><a class="reference internal" href="#runtime-implementation">Runtime implementation</a></li> </ul> </li> <li><a class="reference internal" href="#rejected-ideas">Rejected Ideas</a><ul> <li><a class="reference internal" href="#using-the-functional-syntax-in-annotations">Using the functional syntax in annotations</a></li> <li><a class="reference internal" href="#using-dict-or-typing-dict-with-a-single-type-argument">Using <code class="docutils literal notranslate">dict</code> or <code class="docutils literal notranslate">typing.Dict</code> with a single type argument</a></li> <li><a class="reference internal" href="#using-a-simple-dictionary">Using a simple dictionary</a></li> <li><a class="reference internal" href="#extending-other-typed-dictionaries">Extending other typed dictionaries</a></li> </ul> </li> <li><a class="reference internal" href="#open-issues">Open Issues</a><ul> <li><a class="reference internal" href="#should-inlined-typed-dictionaries-be-proper-classes">Should inlined typed dictionaries be proper classes?</a></li> <li><a class="reference internal" href="#inlined-typed-dictionaries-and-extra-items">Inlined typed dictionaries and extra items</a></li> </ul> </li> <li><a class="reference internal" href="#copyright">Copyright</a></li> </ul> <a id="source" href="https://github.com/python/peps/blob/main/peps/pep-0764.rst">Page Source (GitHub)</a> </nav> </section> <script src="../_static/colour_scheme.js"></script> <script src="../_static/wrap_tables.js"></script> <script src="../_static/sticky_banner.js"></script> </body> </html>