Boolean constructor.
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> [Boolean][mdn-boolean] constructor.
``bash`
npm install @stdlib/boolean-ctor
`javascript`
var Boolean = require( '@stdlib/boolean-ctor' );
#### Boolean( value )
Returns a Boolean object, which is an object wrapper for a primitive boolean value.
`javascript`
var b = new Boolean( null );
// returns
When invoked without new, the function converts an input value to a primitive boolean value.
`javascript`
var b = Boolean( null );
// returns false
*
##### Boolean.prototype.toString()
Returns a string representation of the boolean value.
`javascript`
var b = new Boolean( true );
var str = b.toString();
// returns 'true'
##### Boolean.prototype.valueOf()
Returns the primitive value of the boolean object.
`javascript
var b = new Boolean( true );
var val = b.valueOf();
// returns true
b = new Boolean();
val = b.valueOf();
// returns false
`
- When invoked without new,
- if provided false, null, undefined, -0, 0, NaN, or an empty string, the function returns false.'false'
- if provided any other value, including an empty object, an empty array, the string , or a Boolean object (including a Boolean object whose value is false), the function returns true.
- When invoked with new, the value of the returned Boolean object adheres to the same conversion semantics as when the constructor is invoked without new.
`javascript
var format = require( '@stdlib/string-format' );
var Bool = require( '@stdlib/boolean-ctor' );
var values = [
'5',
5,
0,
NaN,
true,
false,
null,
void 0,
[],
{}
];
var i;
for ( i = 0; i < values.length; i++ ) {
console.log( format( '%s => %s', JSON.stringify( values[ i ] ), ( Bool( values[ i ] ) ) ? 'true' : 'false' ) );
}
`
*
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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[test-url]: https://github.com/stdlib-js/boolean-ctor/actions/workflows/test.yml?query=branch:v0.2.3
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[coverage-url]: https://codecov.io/github/stdlib-js/boolean-ctor?branch=main
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[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[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/boolean-ctor/tree/deno
[deno-readme]: https://github.com/stdlib-js/boolean-ctor/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/boolean-ctor/tree/umd
[umd-readme]: https://github.com/stdlib-js/boolean-ctor/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/boolean-ctor/tree/esm
[esm-readme]: https://github.com/stdlib-js/boolean-ctor/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/boolean-ctor/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/boolean-ctor/main/LICENSE
[mdn-boolean]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean