Detect native WeakMap support.
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> Detect native [WeakMap][mdn-weakmap] support.
``bash`
npm install @stdlib/assert-has-weakmap-support
`javascript`
var hasWeakMapSupport = require( '@stdlib/assert-has-weakmap-support' );
#### hasWeakMapSupport()
Detects if a runtime environment supports ES2015 [WeakMap][mdn-weakmap].
`javascript`
var bool = hasWeakMapSupport();
// returns
`javascript
var hasWeakMapSupport = require( '@stdlib/assert-has-weakmap-support' );
var bool = hasWeakMapSupport();
if ( bool ) {
console.log( 'Environment has WeakMap support.' );
} else {
console.log( 'Environment lacks WeakMap support.' );
}
`
- [@stdlib/assert-has-weakmap-support-cli][@stdlib/assert-has-weakmap-support-cli]: CLI package for use as a command-line utility.
*
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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].
[@stdlib/assert-has-weakmap-support-cli]: https://www.npmjs.com/package/@stdlib/assert-has-weakmap-support-cli
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[test-image]: https://github.com/stdlib-js/assert-has-weakmap-support/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/assert-has-weakmap-support/actions/workflows/test.yml?query=branch:v0.2.3
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/assert-has-weakmap-support/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/assert-has-weakmap-support?branch=main
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[chat-url]: https://stdlib.zulipchat.com
[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[cli-section]: https://github.com/stdlib-js/assert-has-weakmap-support#cli
[cli-url]: https://github.com/stdlib-js/assert-has-weakmap-support/tree/cli
[@stdlib/assert-has-weakmap-support]: https://github.com/stdlib-js/assert-has-weakmap-support/tree/main
[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-has-weakmap-support/tree/deno
[deno-readme]: https://github.com/stdlib-js/assert-has-weakmap-support/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/assert-has-weakmap-support/tree/umd
[umd-readme]: https://github.com/stdlib-js/assert-has-weakmap-support/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/assert-has-weakmap-support/tree/esm
[esm-readme]: https://github.com/stdlib-js/assert-has-weakmap-support/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/assert-has-weakmap-support/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/assert-has-weakmap-support/main/LICENSE
[mdn-weakmap]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap