Test if two arguments are the same value.
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> Test if two arguments are the same value.
``bash`
npm install @stdlib/assert-is-same-value
`javascript`
var isSameValue = require( '@stdlib/assert-is-same-value' );
#### isSameValue( a, b )
Tests if two arguments a and b are the same value.
`javascript
var bool = isSameValue( false, false );
// returns true
bool = isSameValue( '', '' );
// returns true
bool = isSameValue( {}, {} );
// returns false
`
In contrast to the strict equality operator ===, the function distinguishes between +0 and -0 and treats NaNs as the same value.
`javascript
var bool = ( 0.0 === -0.0 );
// returns true
bool = isSameValue( 0.0, -0.0 );
// returns false
bool = isSameValue( -0.0, -0.0 );
// returns true
bool = ( NaN === NaN );
// returns false
bool = isSameValue( NaN, NaN );
// returns true
`
- The function implements the [SameValue Algorithm][ecma-262-same-value-algorithm] (as specified in ECMAScript 5), with support for [complex number][@stdlib/complex] objects.
`javascript
var isSameValue = require( '@stdlib/assert-is-same-value' );
var bool = isSameValue( true, true );
// returns true
bool = isSameValue( true, false );
// returns false
bool = isSameValue( 'beep', 'beep' );
// returns true
bool = isSameValue( 3.14, 3.14 );
// returns true
bool = isSameValue( null, null );
// returns true
bool = isSameValue( 0.0, 0.0 );
// returns true
bool = isSameValue( -0.0, 0.0 );
// returns false
bool = isSameValue( NaN, NaN );
// returns true
bool = isSameValue( {}, {} );
// returns false
bool = isSameValue( [], [] );
// returns false
bool = isSameValue( isSameValue, isSameValue );
// returns true
`
*
- [@stdlib/assert-is-same-value-zero][@stdlib/assert/is-same-value-zero]: test if two arguments are the same value.
- [@stdlib/assert-is-strict-equal][@stdlib/assert/is-strict-equal]: test if two arguments are strictly equal.
*
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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[stdlib]: https://github.com/stdlib-js/stdlib
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[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/assert-is-same-value/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-is-same-value/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-is-same-value/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-is-same-value/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-is-same-value/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-is-same-value/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/assert-is-same-value/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-is-same-value/main/LICENSE
[ecma-262-same-value-algorithm]: http://ecma-international.org/ecma-262/5.1/#sec-9.12
[@stdlib/complex]: https://www.npmjs.com/package/@stdlib/complex
[@stdlib/assert/is-same-value-zero]: https://www.npmjs.com/package/@stdlib/assert-is-same-value-zero
[@stdlib/assert/is-strict-equal]: https://www.npmjs.com/package/@stdlib/assert-is-strict-equal