@stdlib/assert/is-property-key/README.md

Standard assertion utilities.

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# isPropertyKey

> Test whether a value is a property key.

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## Usage

```javascript
var isPropertyKey = require( '@stdlib/assert/is-property-key' );
```

#### isPropertyKey( value )

Tests whether a value is a property key.

```javascript
var bool = isPropertyKey( 'beep' );
// returns true

bool = isPropertyKey( 3.14 );
// returns false
```

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## Notes

-   A valid property key is either a string, symbol, or a nonnegative integer. For example, `'beep'`, `Symbol( 'beep' )`, and `3` are all valid property keys.
-   Only primitive values are considered to be valid property keys. This excludes object wrappers such as `new String( 'beep' )`.

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## Examples

<!-- eslint no-undef: "error" -->

```javascript
var Symbol = require( '@stdlib/symbol/ctor' );
var hasSymbolSupport = require( '@stdlib/assert/has-symbol-support' );
var isPropertyKey = require( '@stdlib/assert/is-property-key' );

var hasSymbols = hasSymbolSupport();
var bool = isPropertyKey( 'beep' );
// returns true

if ( hasSymbols ) {
    bool = isPropertyKey( Symbol( 'beep' ) );
    // returns true
} else {
    console.log( 'Environment does not support symbols.' );
}

bool = isPropertyKey( 37 );
// returns true

bool = isPropertyKey( {} );
// returns false

bool = isPropertyKey( [] );
// returns false
```

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* * *

## See Also

-   <span class="package-name">[`@stdlib/assert/is-string`][@stdlib/assert/is-string]</span><span class="delimiter">: </span><span class="description">test if a value is a string.</span>
-   <span class="package-name">[`@stdlib/assert/is-symbol`][@stdlib/assert/is-symbol]</span><span class="delimiter">: </span><span class="description">test if a value is a symbol.</span>
-   <span class="package-name">[`@stdlib/assert/is-nonnegative-integer`][@stdlib/assert/is-nonnegative-integer]</span><span class="delimiter">: </span><span class="description">test if a value is a number having a nonnegative integer value.</span>
-   <span class="package-name">[`@stdlib/assert/has-own-property`][@stdlib/assert/has-own-property]</span><span class="delimiter">: </span><span class="description">test if an object has a specified property.</span>
-   <span class="package-name">[`@stdlib/assert/has-property`][@stdlib/assert/has-property]</span><span class="delimiter">: </span><span class="description">test if an object has a specified property, either own or inherited.</span>

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[@stdlib/assert/is-string]: https://github.com/stdlib-js/assert/tree/main/is-string

[@stdlib/assert/is-symbol]: https://github.com/stdlib-js/assert/tree/main/is-symbol

[@stdlib/assert/is-nonnegative-integer]: https://github.com/stdlib-js/assert/tree/main/is-nonnegative-integer

[@stdlib/assert/has-own-property]: https://github.com/stdlib-js/assert/tree/main/has-own-property

[@stdlib/assert/has-property]: https://github.com/stdlib-js/assert/tree/main/has-property

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