constant package - go/constant

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href="#Float64Val" title="Float64Val(x)" data-gtmc="doc outline link"> Float64Val(x) </a> </li> <li> <a href="#Int64Val" title="Int64Val(x)" data-gtmc="doc outline link"> Int64Val(x) </a> </li> <li> <a href="#Sign" title="Sign(x)" data-gtmc="doc outline link"> Sign(x) </a> </li> <li> <a href="#StringVal" title="StringVal(x)" data-gtmc="doc outline link"> StringVal(x) </a> </li> <li> <a href="#Uint64Val" title="Uint64Val(x)" data-gtmc="doc outline link"> Uint64Val(x) </a> </li> <li> <a href="#Val" title="Val(x)" data-gtmc="doc outline link"> Val(x) </a> </li> </ul> </li> <li class="DocNav-types"> <a href="#pkg-types" data-gtmc="doc outline link"> Types </a> <ul> <li> <a href="#Kind" title="type Kind" data-gtmc="doc outline link"> type Kind </a> <ul> <li> <a href="#Kind.String" title="(i) String()" data-gtmc="doc outline link"> (i) String() </a> </li> </ul> </li> <li> <a href="#Value" title="type Value" data-gtmc="doc outline link"> type Value </a> <ul> <li> <a href="#BinaryOp" title="BinaryOp(x_, op, y_)" data-gtmc="doc outline link"> BinaryOp(x_, op, y_) </a> </li> <li> <a href="#Denom" title="Denom(x)" data-gtmc="doc outline link"> Denom(x) </a> </li> <li> <a href="#Imag" title="Imag(x)" data-gtmc="doc outline link"> Imag(x) </a> </li> <li> <a href="#Make" title="Make(x)" data-gtmc="doc outline link"> Make(x) </a> </li> <li> <a href="#MakeBool" title="MakeBool(b)" data-gtmc="doc outline link"> MakeBool(b) </a> </li> <li> <a href="#MakeFloat64" title="MakeFloat64(x)" data-gtmc="doc outline link"> MakeFloat64(x) </a> </li> <li> <a href="#MakeFromBytes" title="MakeFromBytes(bytes)" data-gtmc="doc outline link"> MakeFromBytes(bytes) </a> </li> <li> <a href="#MakeFromLiteral" title="MakeFromLiteral(lit, tok, zero)" data-gtmc="doc outline link"> MakeFromLiteral(lit, tok, zero) </a> </li> <li> <a href="#MakeImag" title="MakeImag(x)" data-gtmc="doc outline link"> MakeImag(x) </a> </li> <li> <a href="#MakeInt64" title="MakeInt64(x)" data-gtmc="doc outline link"> MakeInt64(x) </a> </li> <li> <a href="#MakeString" title="MakeString(s)" data-gtmc="doc outline link"> MakeString(s) </a> </li> <li> <a href="#MakeUint64" title="MakeUint64(x)" data-gtmc="doc outline link"> MakeUint64(x) </a> </li> <li> <a href="#MakeUnknown" title="MakeUnknown()" data-gtmc="doc outline link"> MakeUnknown() </a> </li> <li> <a href="#Num" title="Num(x)" data-gtmc="doc outline link"> Num(x) </a> </li> <li> <a href="#Real" title="Real(x)" data-gtmc="doc outline link"> Real(x) </a> </li> <li> <a href="#Shift" title="Shift(x, op, s)" data-gtmc="doc outline link"> Shift(x, op, s) </a> </li> <li> <a href="#ToComplex" title="ToComplex(x)" data-gtmc="doc outline link"> ToComplex(x) </a> </li> <li> <a href="#ToFloat" title="ToFloat(x)" data-gtmc="doc outline link"> ToFloat(x) </a> </li> <li> <a href="#ToInt" title="ToInt(x)" data-gtmc="doc outline link"> ToInt(x) </a> </li> <li> <a href="#UnaryOp" title="UnaryOp(op, y, prec)" data-gtmc="doc outline link"> UnaryOp(op, y, prec) </a> </li> </ul> </li> </ul> </li> </ul> </li> <li> <a href="#section-sourcefiles" data-gtmc="outline link"> Source Files </a> </li> </ul> </div> <div class="go-Main-navMobile js-mainNavMobile"> <label class="go-Label"> <select class="go-Select"> <option selected disabled>Documentation</option> </select> </label> </div> </nav> <article class="go-Main-article js-mainContent"> <div class="UnitDetails" data-test-id="UnitDetails" style="display: block;"> <div class="UnitDetails-content js-unitDetailsContent" data-test-id="UnitDetails-content"> <div class="UnitDoc"> <h2 class="UnitDoc-title" id="section-documentation"> <img class="go-Icon" height="24" width="24" src="/static/shared/icon/code_gm_grey_24dp.svg" alt=""> Documentation <a class="UnitDoc-idLink" href="#section-documentation" aria-label="Go to Documentation">露</a> </h2> <div class="Documentation js-documentation"> <div class="Documentation-content js-docContent"> <section class="Documentation-overview"> <h3 tabindex="-1" id="pkg-overview" class="Documentation-overviewHeader">Overview <a href="#pkg-overview" aria-label="Go to Overview">露</a></h3> <p>Package constant implements Values representing untyped Go constants and their corresponding operations. </p><p>A special Unknown value may be used when a value is unknown due to an error. Operations on unknown values produce unknown values unless specified otherwise. </p> <details tabindex="-1" id="example-package-ComplexNumbers" class="Documentation-exampleDetails js-exampleContainer"> <summary class="Documentation-exampleDetailsHeader">Example (ComplexNumbers) <a href="#example-package-ComplexNumbers" aria-label="Go to Example (ComplexNumbers)">露</a></summary> <div class="Documentation-exampleDetailsBody"> <pre class="Documentation-exampleCode"> package main import ( "fmt" "go/constant" "go/token" ) func main() { // Create the complex number 2.3 + 5i. ar := constant.MakeFloat64(2.3) ai := constant.MakeImag(constant.MakeInt64(5)) a := constant.BinaryOp(ar, token.ADD, ai) // Compute (2.3 + 5i) * 11. b := constant.MakeUint64(11) c := constant.BinaryOp(a, token.MUL, b) // Convert c into a complex128. Ar, exact := constant.Float64Val(constant.Real(c)) if !exact { fmt.Printf("Could not represent real part %s exactly as float64\n", constant.Real(c)) } Ai, exact := constant.Float64Val(constant.Imag(c)) if !exact { fmt.Printf("Could not represent imaginary part %s as exactly as float64\n", constant.Imag(c)) } C := complex(Ar, Ai) fmt.Println("literal", 25.3+55i) fmt.Println("go/constant", c) fmt.Println("complex128", C) } </pre> <pre><span class="Documentation-exampleOutputLabel">Output:</span> <span class="Documentation-exampleOutput"> Could not represent real part 25.3 exactly as float64 literal (25.3+55i) go/constant (25.3 + 55i) complex128 (25.299999999999997+55i) </span></pre> </div> <div class="Documentation-exampleButtonsContainer"> <p class="Documentation-exampleError" role="alert" aria-atomic="true"></p> <button class="Documentation-exampleShareButton" aria-label="Share Code">Share</button> <button class="Documentation-exampleFormatButton" aria-label="Format Code">Format</button> <button class="Documentation-exampleRunButton" aria-label="Run Code">Run</button> </div></details> </section><section class="Documentation-index"> <h3 id="pkg-index" class="Documentation-indexHeader">Index <a href="#pkg-index" aria-label="Go to Index">露</a></h3> <ul class="Documentation-indexList"> <li class="Documentation-indexFunction"> <a href="#BitLen">func BitLen(x Value) int</a></li> <li class="Documentation-indexFunction"> <a href="#BoolVal">func BoolVal(x Value) bool</a></li> <li class="Documentation-indexFunction"> <a href="#Bytes">func Bytes(x Value) []byte</a></li> <li class="Documentation-indexFunction"> <a href="#Compare">func Compare(x_ Value, op token.Token, y_ Value) bool</a></li> <li class="Documentation-indexFunction"> <a href="#Float32Val">func Float32Val(x Value) (float32, bool)</a></li> <li class="Documentation-indexFunction"> <a href="#Float64Val">func Float64Val(x Value) (float64, bool)</a></li> <li class="Documentation-indexFunction"> <a href="#Int64Val">func Int64Val(x Value) (int64, bool)</a></li> <li class="Documentation-indexFunction"> <a href="#Sign">func Sign(x Value) int</a></li> <li class="Documentation-indexFunction"> <a href="#StringVal">func StringVal(x Value) string</a></li> <li class="Documentation-indexFunction"> <a href="#Uint64Val">func Uint64Val(x Value) (uint64, bool)</a></li> <li class="Documentation-indexFunction"> <a href="#Val">func Val(x Value) any</a></li> <li class="Documentation-indexType"> <a href="#Kind">type Kind</a></li> <li><ul class="Documentation-indexTypeMethods"> <li> <a href="#Kind.String">func (i Kind) String() string</a></li> </ul></li> <li class="Documentation-indexType"> <a href="#Value">type Value</a></li> <li><ul class="Documentation-indexTypeFunctions"> <li> <a href="#BinaryOp">func BinaryOp(x_ Value, op token.Token, y_ Value) Value</a></li> <li> <a href="#Denom">func Denom(x Value) Value</a></li> <li> <a href="#Imag">func Imag(x Value) Value</a></li> <li> <a href="#Make">func Make(x any) Value</a></li> <li> <a href="#MakeBool">func MakeBool(b bool) Value</a></li> <li> <a href="#MakeFloat64">func MakeFloat64(x float64) Value</a></li> <li> <a href="#MakeFromBytes">func MakeFromBytes(bytes []byte) Value</a></li> <li> <a href="#MakeFromLiteral">func MakeFromLiteral(lit string, tok token.Token, zero uint) Value</a></li> <li> <a href="#MakeImag">func MakeImag(x Value) Value</a></li> <li> <a href="#MakeInt64">func MakeInt64(x int64) Value</a></li> <li> <a href="#MakeString">func MakeString(s string) Value</a></li> <li> <a href="#MakeUint64">func MakeUint64(x uint64) Value</a></li> <li> <a href="#MakeUnknown">func MakeUnknown() Value</a></li> <li> <a href="#Num">func Num(x Value) Value</a></li> <li> <a href="#Real">func Real(x Value) Value</a></li> <li> <a href="#Shift">func Shift(x Value, op token.Token, s uint) Value</a></li> <li> <a href="#ToComplex">func ToComplex(x Value) Value</a></li> <li> <a href="#ToFloat">func ToFloat(x Value) Value</a></li> <li> <a href="#ToInt">func ToInt(x Value) Value</a></li> <li> <a href="#UnaryOp">func UnaryOp(op token.Token, y Value, prec uint) Value</a></li> </ul></li> </ul> </section><section class="Documentation-examples"> <h4 tabindex="-1" id="pkg-examples" class="Documentation-examplesHeader">Examples <a class="Documentation-idLink" href="#pkg-examples" aria-label="Go to Examples">露</a></h4> <ul class="Documentation-examplesList"> <li><a href="#example-package-ComplexNumbers" class="js-exampleHref">Package (ComplexNumbers)</a></li> <li><a href="#example-BinaryOp" class="js-exampleHref">BinaryOp</a></li> <li><a href="#example-Compare" class="js-exampleHref">Compare</a></li> <li><a href="#example-Sign" class="js-exampleHref">Sign</a></li> <li><a href="#example-UnaryOp" class="js-exampleHref">UnaryOp</a></li> <li><a href="#example-Val" class="js-exampleHref">Val</a></li> </ul> </section><h3 tabindex="-1" id="pkg-constants" class="Documentation-constantsHeader">Constants <a href="#pkg-constants" aria-label="Go to Constants">露</a></h3> <section class="Documentation-constants"><p class="Documentation-empty">This section is empty.</p></section> <h3 tabindex="-1" id="pkg-variables" class="Documentation-variablesHeader">Variables <a href="#pkg-variables" aria-label="Go to Variables">露</a></h3> <section class="Documentation-variables"><p class="Documentation-empty">This section is empty.</p></section> <h3 tabindex="-1" id="pkg-functions" class="Documentation-functionsHeader">Functions <a href="#pkg-functions" aria-label="Go to Functions">露</a></h3> <section class="Documentation-functions"><div class="Documentation-function"> <h4 tabindex="-1" id="BitLen" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=645">BitLen</a> <a class="Documentation-idLink" href="#BitLen" aria-label="Go to BitLen">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func BitLen(x <a href="#Value">Value</a>) <a href="/builtin#int">int</a></pre> </div> <p>BitLen returns the number of bits required to represent the absolute value x in binary representation; x must be an <a href="#Int">Int</a> or an <a href="#Unknown">Unknown</a>. If x is <a href="#Unknown">Unknown</a>, the result is 0. </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="BoolVal" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=480">BoolVal</a> <a class="Documentation-idLink" href="#BoolVal" aria-label="Go to BoolVal">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func BoolVal(x <a href="#Value">Value</a>) <a href="/builtin#bool">bool</a></pre> </div> <p>BoolVal returns the Go boolean value of x, which must be a <a href="#Bool">Bool</a> or an <a href="#Unknown">Unknown</a>. If x is <a href="#Unknown">Unknown</a>, the result is false. </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Bytes" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=702">Bytes</a> <a class="Documentation-idLink" href="#Bytes" aria-label="Go to Bytes">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Bytes(x <a href="#Value">Value</a>) []<a href="/builtin#byte">byte</a></pre> </div> <p>Bytes returns the bytes for the absolute value of x in little- endian binary representation; x must be an <a href="#Int">Int</a>. </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Compare" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=1337">Compare</a> <a class="Documentation-idLink" href="#Compare" aria-label="Go to Compare">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Compare(x_ <a href="#Value">Value</a>, op <a href="/go/token">token</a>.<a href="/go/token#Token">Token</a>, y_ <a href="#Value">Value</a>) <a href="/builtin#bool">bool</a></pre> </div> <p>Compare returns the result of the comparison x op y. The comparison must be defined for the operands. If one of the operands is <a href="#Unknown">Unknown</a>, the result is false. </p> <details tabindex="-1" id="example-Compare" class="Documentation-exampleDetails js-exampleContainer"> <summary class="Documentation-exampleDetailsHeader">Example <a href="#example-Compare" aria-label="Go to Example">露</a></summary> <div class="Documentation-exampleDetailsBody"> <pre class="Documentation-exampleCode"> package main import ( "fmt" "go/constant" "go/token" "slices" ) func main() { vs := []constant.Value{ constant.MakeString("Z"), constant.MakeString("bacon"), constant.MakeString("go"), constant.MakeString("Frame"), constant.MakeString("defer"), constant.MakeFromLiteral(`"a"`, token.STRING, 0), } slices.SortFunc(vs, func(a, b constant.Value) int { if constant.Compare(a, token.LSS, b) { return -1 } if constant.Compare(a, token.GTR, b) { return +1 } return 0 }) for _, v := range vs { fmt.Println(constant.StringVal(v)) } } </pre> <pre><span class="Documentation-exampleOutputLabel">Output:</span> <span class="Documentation-exampleOutput"> Frame Z a bacon defer go </span></pre> </div> <div class="Documentation-exampleButtonsContainer"> <p class="Documentation-exampleError" role="alert" aria-atomic="true"></p> <button class="Documentation-exampleShareButton" aria-label="Share Code">Share</button> <button class="Documentation-exampleFormatButton" aria-label="Format Code">Format</button> <button class="Documentation-exampleRunButton" aria-label="Run Code">Run</button> </div></details> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Float32Val" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=537">Float32Val</a> <a class="Documentation-idLink" href="#Float32Val" aria-label="Go to Float32Val">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Float32Val(x <a href="#Value">Value</a>) (<a href="/builtin#float32">float32</a>, <a href="/builtin#bool">bool</a>)</pre> </div> <p>Float32Val is like <a href="#Float64Val">Float64Val</a> but for float32 instead of float64. </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Float64Val" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=562">Float64Val</a> <a class="Documentation-idLink" href="#Float64Val" aria-label="Go to Float64Val">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Float64Val(x <a href="#Value">Value</a>) (<a href="/builtin#float64">float64</a>, <a href="/builtin#bool">bool</a>)</pre> </div> <p>Float64Val returns the nearest Go float64 value of x and whether the result is exact; x must be numeric or an <a href="#Unknown">Unknown</a>, but not <a href="#Complex">Complex</a>. For values too small (too close to 0) to represent as float64, <a href="#Float64Val">Float64Val</a> silently underflows to 0. The result sign always matches the sign of x, even for 0. If x is <a href="#Unknown">Unknown</a>, the result is (0, false). </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Int64Val" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=507">Int64Val</a> <a class="Documentation-idLink" href="#Int64Val" aria-label="Go to Int64Val">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Int64Val(x <a href="#Value">Value</a>) (<a href="/builtin#int64">int64</a>, <a href="/builtin#bool">bool</a>)</pre> </div> <p>Int64Val returns the Go int64 value of x and whether the result is exact; x must be an <a href="#Int">Int</a> or an <a href="#Unknown">Unknown</a>. If the result is not exact, its value is undefined. If x is <a href="#Unknown">Unknown</a>, the result is (0, false). </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Sign" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=665">Sign</a> <a class="Documentation-idLink" href="#Sign" aria-label="Go to Sign">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Sign(x <a href="#Value">Value</a>) <a href="/builtin#int">int</a></pre> </div> <p>Sign returns -1, 0, or 1 depending on whether x < 0, x == 0, or x > 0; x must be numeric or <a href="#Unknown">Unknown</a>. For complex values x, the sign is 0 if x == 0, otherwise it is != 0. If x is <a href="#Unknown">Unknown</a>, the result is 1. </p> <details tabindex="-1" id="example-Sign" class="Documentation-exampleDetails js-exampleContainer"> <summary class="Documentation-exampleDetailsHeader">Example <a href="#example-Sign" aria-label="Go to Example">露</a></summary> <div class="Documentation-exampleDetailsBody"> <pre class="Documentation-exampleCode"> package main import ( "fmt" "go/constant" "go/token" ) func main() { zero := constant.MakeInt64(0) one := constant.MakeInt64(1) negOne := constant.MakeInt64(-1) mkComplex := func(a, b constant.Value) constant.Value { b = constant.MakeImag(b) return constant.BinaryOp(a, token.ADD, b) } vs := []constant.Value{ negOne, mkComplex(zero, negOne), mkComplex(one, negOne), mkComplex(negOne, one), mkComplex(negOne, negOne), zero, mkComplex(zero, zero), one, mkComplex(zero, one), mkComplex(one, one), } for _, v := range vs { fmt.Printf("% d %s\n", constant.Sign(v), v) } } </pre> <pre><span class="Documentation-exampleOutputLabel">Output:</span> <span class="Documentation-exampleOutput"> -1 -1 -1 (0 + -1i) -1 (1 + -1i) -1 (-1 + 1i) -1 (-1 + -1i) 0 0 0 (0 + 0i) 1 1 1 (0 + 1i) 1 (1 + 1i) </span></pre> </div> <div class="Documentation-exampleButtonsContainer"> <p class="Documentation-exampleError" role="alert" aria-atomic="true"></p> <button class="Documentation-exampleShareButton" aria-label="Share Code">Share</button> <button class="Documentation-exampleFormatButton" aria-label="Format Code">Format</button> <button class="Documentation-exampleRunButton" aria-label="Run Code">Run</button> </div></details> </div><div class="Documentation-function"> <h4 tabindex="-1" id="StringVal" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=493">StringVal</a> <a class="Documentation-idLink" href="#StringVal" aria-label="Go to StringVal">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func StringVal(x <a href="#Value">Value</a>) <a href="/builtin#string">string</a></pre> </div> <p>StringVal returns the Go string value of x, which must be a <a href="#String">String</a> or an <a href="#Unknown">Unknown</a>. If x is <a href="#Unknown">Unknown</a>, the result is "". </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Uint64Val" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=523">Uint64Val</a> <a class="Documentation-idLink" href="#Uint64Val" aria-label="Go to Uint64Val">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Uint64Val(x <a href="#Value">Value</a>) (<a href="/builtin#uint64">uint64</a>, <a href="/builtin#bool">bool</a>)</pre> </div> <p>Uint64Val returns the Go uint64 value of x and whether the result is exact; x must be an <a href="#Int">Int</a> or an <a href="#Unknown">Unknown</a>. If the result is not exact, its value is undefined. If x is <a href="#Unknown">Unknown</a>, the result is (0, false). </p> </div><div class="Documentation-function"> <h4 tabindex="-1" id="Val" data-kind="function" class="Documentation-functionHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=593">Val</a> <a class="Documentation-idLink" href="#Val" aria-label="Go to Val">露</a></span> <span class="Documentation-sinceVersion"> <span class="Documentation-sinceVersionLabel">added in</span> <span class="Documentation-sinceVersionVersion">go1.13</span> </span> </h4> <div class="Documentation-declaration"> <pre>func Val(x <a href="#Value">Value</a>) <a href="/builtin#any">any</a></pre> </div> <p>Val returns the underlying value for a given constant. Since it returns an interface, it is up to the caller to type assert the result to the expected type. The possible dynamic return types are: </p><pre>x Kind type of result ----------------------------------------- Bool bool String string Int int64 or *big.Int Float *big.Float or *big.Rat everything else nil </pre> <details tabindex="-1" id="example-Val" class="Documentation-exampleDetails js-exampleContainer"> <summary class="Documentation-exampleDetailsHeader">Example <a href="#example-Val" aria-label="Go to Example">露</a></summary> <div class="Documentation-exampleDetailsBody"> <pre class="Documentation-exampleCode"> package main import ( "fmt" "go/constant" "math" ) func main() { maxint := constant.MakeInt64(math.MaxInt64) fmt.Printf("%v\n", constant.Val(maxint)) e := constant.MakeFloat64(math.E) fmt.Printf("%v\n", constant.Val(e)) b := constant.MakeBool(true) fmt.Printf("%v\n", constant.Val(b)) b = constant.Make(false) fmt.Printf("%v\n", constant.Val(b)) } </pre> <pre><span class="Documentation-exampleOutputLabel">Output:</span> <span class="Documentation-exampleOutput"> 9223372036854775807 6121026514868073/2251799813685248 true false </span></pre> </div> <div class="Documentation-exampleButtonsContainer"> <p class="Documentation-exampleError" role="alert" aria-atomic="true"></p> <button class="Documentation-exampleShareButton" aria-label="Share Code">Share</button> <button class="Documentation-exampleFormatButton" aria-label="Format Code">Format</button> <button class="Documentation-exampleRunButton" aria-label="Run Code">Run</button> </div></details> </div></section> <h3 tabindex="-1" id="pkg-types" class="Documentation-typesHeader">Types <a href="#pkg-types" aria-label="Go to Types">露</a></h3> <section class="Documentation-types"><div class="Documentation-type"> <h4 tabindex="-1" id="Kind" data-kind="type" class="Documentation-typeHeader"> <span>type <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=29">Kind</a> <a class="Documentation-idLink" href="#Kind" aria-label="Go to Kind">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>type Kind <a href="/builtin#int">int</a></pre> </div> <p>Kind specifies the kind of value represented by a <a href="#Value">Value</a>. </p> <div class="Documentation-typeConstant"> <div class="Documentation-declaration"> <pre>const ( <span id="Unknown" data-kind="constant"> <span class="comment">// unknown values</span> </span> Unknown <a href="#Kind">Kind</a> = <a href="/builtin#iota">iota</a> <span class="comment">// non-numeric values</span> <span id="Bool" data-kind="constant"> Bool </span><span id="String" data-kind="constant"> String </span> <span class="comment">// numeric values</span> <span id="Int" data-kind="constant"> Int </span><span id="Float" data-kind="constant"> Float </span><span id="Complex" data-kind="constant"> Complex </span>)</pre> </div> </div><div class="Documentation-typeMethod"> <h4 tabindex="-1" id="Kind.String" data-kind="method" class="Documentation-typeMethodHeader"> <span>func (Kind) <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/kind_string.go;l=23">String</a> <a class="Documentation-idLink" href="#Kind.String" aria-label="Go to Kind.String">露</a></span> <span class="Documentation-sinceVersion"> <span class="Documentation-sinceVersionLabel">added in</span> <span class="Documentation-sinceVersionVersion">go1.18</span> </span> </h4> <div class="Documentation-declaration"> <pre>func (i <a href="#Kind">Kind</a>) String() <a href="/builtin#string">string</a></pre> </div> </div> </div><div class="Documentation-type"> <h4 tabindex="-1" id="Value" data-kind="type" class="Documentation-typeHeader"> <span>type <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=46">Value</a> <a class="Documentation-idLink" href="#Value" aria-label="Go to Value">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>type Value interface { <span id="Value.Kind" data-kind="method"> <span class="comment">// Kind returns the value kind.</span> </span> Kind() <a href="#Kind">Kind</a> <span id="Value.String" data-kind="method"> <span class="comment">// String returns a short, quoted (human-readable) form of the value.</span> </span> <span class="comment">// For numeric values, the result may be an approximation;</span> <span class="comment">// for String values the result may be a shortened string.</span> <span class="comment">// Use ExactString for a string representing a value exactly.</span> String() <a href="/builtin#string">string</a> <span id="Value.ExactString" data-kind="method"> <span class="comment">// ExactString returns an exact, quoted (human-readable) form of the value.</span> </span> <span class="comment">// If the Value is of Kind String, use StringVal to obtain the unquoted string.</span> ExactString() <a href="/builtin#string">string</a> <span class="comment">// contains filtered or unexported methods</span> }</pre> </div> <p>A Value represents the value of a Go constant. </p> <div class="Documentation-typeFunc"> <h4 tabindex="-1" id="BinaryOp" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=1103">BinaryOp</a> <a class="Documentation-idLink" href="#BinaryOp" aria-label="Go to BinaryOp">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func BinaryOp(x_ <a href="#Value">Value</a>, op <a href="/go/token">token</a>.<a href="/go/token#Token">Token</a>, y_ <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>BinaryOp returns the result of the binary expression x op y. The operation must be defined for the operands. If one of the operands is <a href="#Unknown">Unknown</a>, the result is <a href="#Unknown">Unknown</a>. BinaryOp doesn't handle comparisons or shifts; use <a href="#Compare">Compare</a> or <a href="#Shift">Shift</a> instead. </p><p>To force integer division of <a href="#Int">Int</a> operands, use op == <a href="/go/token#QUO_ASSIGN">token.QUO_ASSIGN</a> instead of <a href="/go/token#QUO">token.QUO</a>; the result is guaranteed to be <a href="#Int">Int</a> in this case. Division by zero leads to a run-time panic. </p> <details tabindex="-1" id="example-BinaryOp" class="Documentation-exampleDetails js-exampleContainer"> <summary class="Documentation-exampleDetailsHeader">Example <a href="#example-BinaryOp" aria-label="Go to Example">露</a></summary> <div class="Documentation-exampleDetailsBody"> <pre class="Documentation-exampleCode"> package main import ( "fmt" "go/constant" "go/token" ) func main() { // 11 / 0.5 a := constant.MakeUint64(11) b := constant.MakeFloat64(0.5) c := constant.BinaryOp(a, token.QUO, b) fmt.Println(c) } </pre> <pre><span class="Documentation-exampleOutputLabel">Output:</span> <span class="Documentation-exampleOutput">22 </span></pre> </div> <div class="Documentation-exampleButtonsContainer"> <p class="Documentation-exampleError" role="alert" aria-atomic="true"></p> <button class="Documentation-exampleShareButton" aria-label="Share Code">Share</button> <button class="Documentation-exampleFormatButton" aria-label="Format Code">Format</button> <button class="Documentation-exampleRunButton" aria-label="Run Code">Run</button> </div></details> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="Denom" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=788">Denom</a> <a class="Documentation-idLink" href="#Denom" aria-label="Go to Denom">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Denom(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>Denom returns the denominator of x; x must be <a href="#Int">Int</a>, <a href="#Float">Float</a>, or <a href="#Unknown">Unknown</a>. If x is <a href="#Unknown">Unknown</a>, or if it is too large or small to represent as a fraction, the result is <a href="#Unknown">Unknown</a>. Otherwise the result is an <a href="#Int">Int</a> >= 1. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="Imag" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=836">Imag</a> <a class="Documentation-idLink" href="#Imag" aria-label="Go to Imag">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Imag(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>Imag returns the imaginary part of x, which must be a numeric or unknown value. If x is <a href="#Unknown">Unknown</a>, the result is <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="Make" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=623">Make</a> <a class="Documentation-idLink" href="#Make" aria-label="Go to Make">露</a></span> <span class="Documentation-sinceVersion"> <span class="Documentation-sinceVersionLabel">added in</span> <span class="Documentation-sinceVersionVersion">go1.13</span> </span> </h4> <div class="Documentation-declaration"> <pre>func Make(x <a href="/builtin#any">any</a>) <a href="#Value">Value</a></pre> </div> <p>Make returns the <a href="#Value">Value</a> for x. </p><pre>type of x result Kind ---------------------------- bool Bool string String int64 Int *big.Int Int *big.Float Float *big.Rat Float anything else Unknown </pre> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeBool" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=386">MakeBool</a> <a class="Documentation-idLink" href="#MakeBool" aria-label="Go to MakeBool">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeBool(b <a href="/builtin#bool">bool</a>) <a href="#Value">Value</a></pre> </div> <p>MakeBool returns the <a href="#Bool">Bool</a> value for b. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeFloat64" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=412">MakeFloat64</a> <a class="Documentation-idLink" href="#MakeFloat64" aria-label="Go to MakeFloat64">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeFloat64(x <a href="/builtin#float64">float64</a>) <a href="#Value">Value</a></pre> </div> <p>MakeFloat64 returns the <a href="#Float">Float</a> value for x. If x is -0.0, the result is 0.0. If x is not finite, the result is an <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeFromBytes" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=734">MakeFromBytes</a> <a class="Documentation-idLink" href="#MakeFromBytes" aria-label="Go to MakeFromBytes">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeFromBytes(bytes []<a href="/builtin#byte">byte</a>) <a href="#Value">Value</a></pre> </div> <p>MakeFromBytes returns the <a href="#Int">Int</a> value given the bytes of its little-endian binary representation. An empty byte slice argument represents 0. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeFromLiteral" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=427">MakeFromLiteral</a> <a class="Documentation-idLink" href="#MakeFromLiteral" aria-label="Go to MakeFromLiteral">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeFromLiteral(lit <a href="/builtin#string">string</a>, tok <a href="/go/token">token</a>.<a href="/go/token#Token">Token</a>, zero <a href="/builtin#uint">uint</a>) <a href="#Value">Value</a></pre> </div> <p>MakeFromLiteral returns the corresponding integer, floating-point, imaginary, character, or string value for a Go literal string. The tok value must be one of <a href="/go/token#INT">token.INT</a>, <a href="/go/token#FLOAT">token.FLOAT</a>, <a href="/go/token#IMAG">token.IMAG</a>, <a href="/go/token#CHAR">token.CHAR</a>, or <a href="/go/token#STRING">token.STRING</a>. The final argument must be zero. If the literal string syntax is invalid, the result is an <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeImag" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=810">MakeImag</a> <a class="Documentation-idLink" href="#MakeImag" aria-label="Go to MakeImag">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeImag(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>MakeImag returns the <a href="#Complex">Complex</a> value x*i; x must be <a href="#Int">Int</a>, <a href="#Float">Float</a>, or <a href="#Unknown">Unknown</a>. If x is <a href="#Unknown">Unknown</a>, the result is <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeInt64" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=399">MakeInt64</a> <a class="Documentation-idLink" href="#MakeInt64" aria-label="Go to MakeInt64">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeInt64(x <a href="/builtin#int64">int64</a>) <a href="#Value">Value</a></pre> </div> <p>MakeInt64 returns the <a href="#Int">Int</a> value for x. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeString" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=389">MakeString</a> <a class="Documentation-idLink" href="#MakeString" aria-label="Go to MakeString">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeString(s <a href="/builtin#string">string</a>) <a href="#Value">Value</a></pre> </div> <p>MakeString returns the <a href="#String">String</a> value for s. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeUint64" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=402">MakeUint64</a> <a class="Documentation-idLink" href="#MakeUint64" aria-label="Go to MakeUint64">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeUint64(x <a href="/builtin#uint64">uint64</a>) <a href="#Value">Value</a></pre> </div> <p>MakeUint64 returns the <a href="#Int">Int</a> value for x. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="MakeUnknown" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=383">MakeUnknown</a> <a class="Documentation-idLink" href="#MakeUnknown" aria-label="Go to MakeUnknown">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func MakeUnknown() <a href="#Value">Value</a></pre> </div> <p>MakeUnknown returns the <a href="#Unknown">Unknown</a> value. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="Num" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=766">Num</a> <a class="Documentation-idLink" href="#Num" aria-label="Go to Num">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Num(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>Num returns the numerator of x; x must be <a href="#Int">Int</a>, <a href="#Float">Float</a>, or <a href="#Unknown">Unknown</a>. If x is <a href="#Unknown">Unknown</a>, or if it is too large or small to represent as a fraction, the result is <a href="#Unknown">Unknown</a>. Otherwise the result is an <a href="#Int">Int</a> with the same sign as x. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="Real" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=823">Real</a> <a class="Documentation-idLink" href="#Real" aria-label="Go to Real">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Real(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>Real returns the real part of x, which must be a numeric or unknown value. If x is <a href="#Unknown">Unknown</a>, the result is <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="Shift" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=1282">Shift</a> <a class="Documentation-idLink" href="#Shift" aria-label="Go to Shift">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func Shift(x <a href="#Value">Value</a>, op <a href="/go/token">token</a>.<a href="/go/token#Token">Token</a>, s <a href="/builtin#uint">uint</a>) <a href="#Value">Value</a></pre> </div> <p>Shift returns the result of the shift expression x op s with op == <a href="/go/token#SHL">token.SHL</a> or <a href="/go/token#SHR">token.SHR</a> (<< or >>). x must be an <a href="#Int">Int</a> or an <a href="#Unknown">Unknown</a>. If x is <a href="#Unknown">Unknown</a>, the result is x. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="ToComplex" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=929">ToComplex</a> <a class="Documentation-idLink" href="#ToComplex" aria-label="Go to ToComplex">露</a></span> <span class="Documentation-sinceVersion"> <span class="Documentation-sinceVersionLabel">added in</span> <span class="Documentation-sinceVersionVersion">go1.6</span> </span> </h4> <div class="Documentation-declaration"> <pre>func ToComplex(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>ToComplex converts x to a <a href="#Complex">Complex</a> value if x is representable as a <a href="#Complex">Complex</a>. Otherwise it returns an <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="ToFloat" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=908">ToFloat</a> <a class="Documentation-idLink" href="#ToFloat" aria-label="Go to ToFloat">露</a></span> <span class="Documentation-sinceVersion"> <span class="Documentation-sinceVersionLabel">added in</span> <span class="Documentation-sinceVersionVersion">go1.6</span> </span> </h4> <div class="Documentation-declaration"> <pre>func ToFloat(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>ToFloat converts x to a <a href="#Float">Float</a> value if x is representable as a <a href="#Float">Float</a>. Otherwise it returns an <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="ToInt" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=854">ToInt</a> <a class="Documentation-idLink" href="#ToInt" aria-label="Go to ToInt">露</a></span> <span class="Documentation-sinceVersion"> <span class="Documentation-sinceVersionLabel">added in</span> <span class="Documentation-sinceVersionVersion">go1.6</span> </span> </h4> <div class="Documentation-declaration"> <pre>func ToInt(x <a href="#Value">Value</a>) <a href="#Value">Value</a></pre> </div> <p>ToInt converts x to an <a href="#Int">Int</a> value if x is representable as an <a href="#Int">Int</a>. Otherwise it returns an <a href="#Unknown">Unknown</a>. </p> </div><div class="Documentation-typeFunc"> <h4 tabindex="-1" id="UnaryOp" data-kind="function" class="Documentation-typeFuncHeader"> <span>func <a class="Documentation-source" href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant/value.go;l=958">UnaryOp</a> <a class="Documentation-idLink" href="#UnaryOp" aria-label="Go to UnaryOp">露</a></span> <span class="Documentation-sinceVersion"> </span> </h4> <div class="Documentation-declaration"> <pre>func UnaryOp(op <a href="/go/token">token</a>.<a href="/go/token#Token">Token</a>, y <a href="#Value">Value</a>, prec <a href="/builtin#uint">uint</a>) <a href="#Value">Value</a></pre> </div> <p>UnaryOp returns the result of the unary expression op y. The operation must be defined for the operand. If prec > 0 it specifies the ^ (xor) result size in bits. If y is <a href="#Unknown">Unknown</a>, the result is <a href="#Unknown">Unknown</a>. </p> <details tabindex="-1" id="example-UnaryOp" class="Documentation-exampleDetails js-exampleContainer"> <summary class="Documentation-exampleDetailsHeader">Example <a href="#example-UnaryOp" aria-label="Go to Example">露</a></summary> <div class="Documentation-exampleDetailsBody"> <pre class="Documentation-exampleCode"> package main import ( "fmt" "go/constant" "go/token" ) func main() { vs := []constant.Value{ constant.MakeBool(true), constant.MakeFloat64(2.7), constant.MakeUint64(42), } for i, v := range vs { switch v.Kind() { case constant.Bool: vs[i] = constant.UnaryOp(token.NOT, v, 0) case constant.Float: vs[i] = constant.UnaryOp(token.SUB, v, 0) case constant.Int: // Use 16-bit precision. // This would be equivalent to ^uint16(v). vs[i] = constant.UnaryOp(token.XOR, v, 16) } } for _, v := range vs { fmt.Println(v) } } </pre> <pre><span class="Documentation-exampleOutputLabel">Output:</span> <span class="Documentation-exampleOutput"> false -2.7 65493 </span></pre> </div> <div class="Documentation-exampleButtonsContainer"> <p class="Documentation-exampleError" role="alert" aria-atomic="true"></p> <button class="Documentation-exampleShareButton" aria-label="Share Code">Share</button> <button class="Documentation-exampleFormatButton" aria-label="Format Code">Format</button> <button class="Documentation-exampleRunButton" aria-label="Run Code">Run</button> </div></details> </div> </div></section></div> </div> </div> <div class="UnitFiles js-unitFiles"> <h2 class="UnitFiles-title" id="section-sourcefiles"> <img class="go-Icon" height="24" width="24" src="/static/shared/icon/insert_drive_file_gm_grey_24dp.svg" alt=""> Source Files <a class="UnitFiles-idLink" href="#section-sourcefiles" aria-label="Go to Source Files">露</a> </h2> <div class="UnitFiles-titleLink"> <a href="https://cs.opensource.google/go/go/+/go1.23.3:src/go/constant" target="_blank" rel="noopener">View all Source 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