npm package: @stdlib/utils-curry
Description: Transform a function into a sequence of functions each accepting a single argument.
Author: The Stdlib Authors
Latest version: 0.2.3

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<details>
  <summary>
    About stdlib...
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</details>

# curry

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

> Transform a function into a sequence of functions each accepting a single argument.

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

<!-- /.intro -->

<!-- Package usage documentation. -->

<section class="installation">

## Installation

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

</section>

<section class="usage">

## Usage

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

#### curry( fcn\[, arity]\[, thisArg] )

Transforms a function into a sequence of functions each accepting a single argument.

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

var fcn = curry( add );

var sum = fcn( 2 )( 3 );
// returns 5
```

By default, `arity` is equal to `fcn.length`. For functions without explicit parameters, provide an `arity` argument.

```javascript
function add() {
    return arguments[ 0 ] + arguments[ 1 ];
}

var fcn = curry( add, 2 );

var sum = fcn( 2 )( 3 );
// returns 5
```

To specify the curried function execution context, provide a `thisArg` argument.

<!-- eslint-disable no-restricted-syntax -->

```javascript
var obj = {
    'name': 'Ada',
    'greet': function greet( word1, word2 ) {
        return word1 + ' ' + word2 + ', ' + this.name + '!';
    }
};

var fcn = curry( obj.greet, obj );

var str = fcn( 'Hello' )( 'there' );
// returns 'Hello there, Ada!'
```

The function supports providing both an `arity` and execution context.

<!-- eslint-disable no-restricted-syntax -->

```javascript
var obj = {
    'name': 'Ada',
    'greet': function greet() {
        return arguments[ 0 ] + ' ' + arguments[ 1 ] + ', ' + this.name + '!';
    }
};

var fcn = curry( obj.greet, 2, obj );

var str = fcn( 'Hello' )( 'there' );
// returns 'Hello there, Ada!'
```

</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

-   Until return value resolution, each invocation returns a new partially applied curry function.

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

    var fcn = curry( add );

    var s0 = fcn( 1 )( 2 )( 3 );
    // returns 6

    s0 = fcn( -1 )( -2 )( -3 );
    // returns -6

    s0 = fcn( 10 )( 20 )( 30 );
    // returns 60

    // Return a partially applied curry function:
    var f1 = fcn( 3 );

    var s1 = f1( 4 )( 5 );
    // returns 12

    s1 = f1( 6 )( 7 );
    // returns 16

    s1 = f1( 8 )( 9 );
    // returns 20

    // Return a partially applied curry function:
    var f2 = fcn( 4 )( 5 );

    var s2 = f2( 6 );
    // returns 15

    s2 = f2( 70 );
    // returns 79

    s2 = f2( 700 );
    // returns 709
    ```

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

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

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

var fcn;
var out;
var i;

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

fcn = curry( add );
out = fcn;
for ( i = 0; i < add.length; i++ ) {
    out = out( i*10 );
}
console.log( out );
```

</section>

<!-- /.examples -->

<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="references">

</section>

<!-- /.references -->

<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

* * *

## See Also

-   <span class="package-name">[`@stdlib/utils-curry-right`][@stdlib/utils/curry-right]</span><span class="delimiter">: </span><span class="description">transform a function into a sequence of functions each accepting a single argument.</span>
-   <span class="package-name">[`@stdlib/utils-uncurry`][@stdlib/utils/uncurry]</span><span class="delimiter">: </span><span class="description">transform a curried function into a function invoked with multiple arguments.</span>
-   <span class="package-name">[`@stdlib/utils-uncurry-right`][@stdlib/utils/uncurry-right]</span><span class="delimiter">: </span><span class="description">transform a curried function into a function invoked with multiple arguments.</span>

</section>

<!-- /.related -->

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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].

</section>

<!-- /.stdlib -->

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[npm-url]: https://npmjs.org/package/@stdlib/utils-curry

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[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/utils-curry/main.svg
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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-curry/tree/deno
[deno-readme]: https://github.com/stdlib-js/utils-curry/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/utils-curry/tree/umd
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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/utils-curry/main/LICENSE

<!-- <related-links> -->

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

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

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

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</section>

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