@stdlib/utils/function-sequence/README.md

Standard utilities.

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# funseq

> Function sequence.

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## Usage

```javascript
var funseq = require( '@stdlib/utils/function-sequence' );
```

#### funseq( ...fcn )

Returns a pipeline function. Starting from the left, the pipeline function evaluates each function and passes the result as an argument to the next function. The result of the rightmost function is the result of the whole.

```javascript
function a( x ) {
    return 2 * x;
}

function b( x ) {
    return x + 3;
}

function c( x ) {
    return x / 5;
}

var f = funseq( a, b, c );

var z = f( 6 ); // ((2*x)+3)/5
// returns 3
```

**Only** the leftmost function is explicitly permitted to accept multiple arguments. All other functions are evaluated as **unary** functions.

```javascript
function a( x, y ) {
    return (x*5) + (y*3);
}

function b( r ) {
    return r + 12;
}

var f = funseq( a, b );

var z = f( 4, 6 );
// returns 50
```

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## Notes

-   The function will throw if provided fewer than `2` input arguments.
-   The difference between this function and [`compose`][@stdlib/utils/compose] is that this function evaluates input arguments from left-to-right, rather than right-to-left.

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## Examples

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

```javascript
var funseq = require( '@stdlib/utils/function-sequence' );

function a( x, y ) {
    return x * y;
}

function b( z ) {
    return z + 5;
}

function c( r ) {
    return r / 10;
}

var f = funseq( a, b, c );

var v = f( 5, 3 );
// returns 2
```

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* * *

## See Also

-   <span class="package-name">[`@stdlib/utils/compose`][@stdlib/utils/compose]</span><span class="delimiter">: </span><span class="description">function composition.</span>
-   <span class="package-name">[`@stdlib/utils/async/function-sequence`][@stdlib/utils/async/function-sequence]</span><span class="delimiter">: </span><span class="description">function sequence.</span>

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[@stdlib/utils/compose]: https://github.com/stdlib-js/utils/tree/main/compose

[@stdlib/utils/async/function-sequence]: https://github.com/stdlib-js/utils/tree/main/async/function-sequence

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