@stdlib/string/base/for-each/README.md

String manipulation functions.

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# forEach

> Invokes a function for each UTF-16 code unit in a string.

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## Usage

```javascript
var forEach = require( '@stdlib/string/base/for-each' );
```

#### forEach( str, clbk\[, thisArg ] )

Invokes a function for each UTF-16 code unit in a string.

```javascript
function log( value, index ) {
    console.log( '%d: %s', index, value );
}

forEach( 'Beep!', log );
/* =>
    0: B
    1: e
    2: e
    3: p
    4: !
*/
```

The invoked function is provided three arguments:

-   **value**: character.
-   **index**: character index.
-   **str**: input string.

To set the function execution context, provide a `thisArg`.

```javascript
function clbk() {
    this.count += 1;
}

var str = '👉🏿';

var ctx = {
    'count': 0
};

forEach( str, clbk, ctx );

var cnt = ctx.count;
// returns 4
```

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## Examples

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

```javascript
var forEach = require( '@stdlib/string/base/for-each' );

function log( value, index ) {
    console.log( '%d: %s', index, value );
}

forEach( 'presidential election', log );
forEach( 'Iñtërnâtiônàlizætiøn', log );
forEach( '🌷🍕', log );
forEach( '\uD834\uDD1E', log );
```

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* * *

## See Also

-   <span class="package-name">[`@stdlib/string/base/for-each-code-point`][@stdlib/string/base/for-each-code-point]</span><span class="delimiter">: </span><span class="description">invoke a function for each Unicode code point in a string.</span>
-   <span class="package-name">[`@stdlib/string/base/for-each-grapheme-cluster`][@stdlib/string/base/for-each-grapheme-cluster]</span><span class="delimiter">: </span><span class="description">invoke a function for each grapheme cluster (i.e., user-perceived character) in a string.</span>
-   <span class="package-name">[`@stdlib/string/for-each`][@stdlib/string/for-each]</span><span class="delimiter">: </span><span class="description">invoke a function for each character in a string.</span>

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[@stdlib/string/base/for-each-code-point]: https://github.com/stdlib-js/string/tree/main/base/for-each-code-point

[@stdlib/string/base/for-each-grapheme-cluster]: https://github.com/stdlib-js/string/tree/main/base/for-each-grapheme-cluster

[@stdlib/string/for-each]: https://github.com/stdlib-js/string/tree/main/for-each

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