naryFunction

Create a function that invokes a provided function with a specified number of arguments.

Installation

npm install @stdlib/utils-nary-function

Usage

var naryFunction = require( '@stdlib/utils-nary-function' );

naryFunction( fcn, arity[, thisArg] )

Returns a function that invokes a provided function with a specified number of arguments.

function sum() {
    var s;
    var i;

    s = 0;
    for ( i = 0; i < arguments.length; i++ ) {
        s += arguments[ i ];
    }
    return s;
}

var fcn = naryFunction( sum, 2 );

var out = fcn( -1, -2, 3 );
// returns -3

To set the this context when invoking the provided function, provide a thisArg.

function Foo() {
    this.scalar = 1;
}

Foo.prototype.sum = function sum() {
    var s;
    var i;

    s = 0;
    for ( i = 0; i < arguments.length; i++ ) {
        s += arguments[ i ] * this.scalar;
    }
    return s;
};

var ctx = {
    'scalar': 3
};

var foo = new Foo();

var fcn = naryFunction( foo.sum, 2, ctx );

var out = fcn( 1, 2, 3 );
// returns 9

Notes

• The returned function always invokes the wrapped function with a specified number of arguments, even when the returned function is provided fewer arguments. The value for the missing arguments is equal to undefined.

Examples

var filledarrayBy = require( '@stdlib/array-filled-by' );
var naryFunction = require( '@stdlib/utils-nary-function' );

function fill( i ) {
    return i;
}

function sum() {
    var s;
    var i;

    s = 0;
    for ( i = 0; i < arguments.length; i++ ) {
        s += arguments[ i ];
    }
    return s;
}

// Create a data array:
var x = filledarrayBy( 10, 'float64', fill );

// Compute cumulative sums...
var f;
var i;
for ( i = 0; i <= x.length; i++ ) {
    f = naryFunction( sum, i );
    console.log( 'sum_%d = %d', i, f.apply( null, x ) );
}

See Also

• @stdlib/utils-mask-arguments: create a function that invokes a provided function according to an argument mask.
• @stdlib/utils-pick-arguments: create a function that invokes a provided function with specified arguments.

Notice

This package is part of 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, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.