npm package: @stdlib/utils-papply
Description: Partially apply function arguments.
Author: The Stdlib Authors
Latest version: 0.2.3

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# papply

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> Partially apply function arguments.

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<section class="intro">

</section>

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<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/utils-papply
```

</section>

<section class="usage">

## Usage

```javascript
var papply = require( '@stdlib/utils-papply' );
```

#### papply( fcn\[, ...args] )

Partially applies function arguments.

```javascript
function add( x, y ) {
    return x + y;
}

var add2 = papply( add, 2 );

var sum = add2( 3 );
// returns 5

sum = add2( 7 );
// returns 9
```

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## Notes

-   The implementation does **not** set the `length` of the returned function. Accordingly, the returned function `length` is **always** `0`.
-   The evaluation context is **always** `null`.

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

```javascript
var randu = require( '@stdlib/random-base-randu' );
var floor = require( '@stdlib/math-base-special-floor' );
var papply = require( '@stdlib/utils-papply' );

var fcn;
var w;
var t;
var s;
var v;
var i;

function add( x, y, z, w, t, s ) {
    return x + y + z + w + t + s;
}

fcn = papply( add, 5, 4, 3 );

for ( i = 0; i < 100; i++ ) {
    w = floor( randu() * 5 );
    t = floor( randu() * 10 );
    s = floor( randu() * 15 );
    v = fcn( w, t, s );
    console.log( '5+4+3+%d+%d+%d = %d', w, t, s, v );
}
```

</section>

<!-- /.examples -->

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</section>

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<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/utils-papply-right`][@stdlib/utils/papply-right]</span><span class="delimiter">: </span><span class="description">partially apply function arguments from the right.</span>

</section>

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<section class="main-repo" >

* * *

## Notice

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].

#### Community

[![Chat][chat-image]][chat-url]

---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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[npm-image]: http://img.shields.io/npm/v/@stdlib/utils-papply.svg
[npm-url]: https://npmjs.org/package/@stdlib/utils-papply

[test-image]: https://github.com/stdlib-js/utils-papply/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/utils-papply/actions/workflows/test.yml?query=branch:v0.2.3

[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/utils-papply/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/utils-papply?branch=main

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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/utils-papply/tree/deno
[deno-readme]: https://github.com/stdlib-js/utils-papply/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/utils-papply/tree/umd
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/utils-papply/main/LICENSE

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[@stdlib/utils/papply-right]: https://www.npmjs.com/package/@stdlib/utils-papply-right

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</section>

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