time-to-botec

Benchmark sampling in different programming languages
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uncurry.js (3278B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2018 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // MODULES //
     22 
     23 var isFunction = require( '@stdlib/assert/is-function' );
     24 var isPositiveInteger = require( '@stdlib/assert/is-positive-integer' ).isPrimitive;
     25 
     26 
     27 // MAIN //
     28 
     29 /**
     30 * Transforms a curried function into a function invoked with multiple arguments.
     31 *
     32 * @param {Function} fcn - curried function
     33 * @param {PositiveInteger} [arity] - number of parameters
     34 * @param {*} [thisArg] - evaluation context
     35 * @throws {TypeError} first argument must be a function
     36 * @throws {TypeError} `arity` argument must be a positive integer
     37 * @returns {Function} uncurried function
     38 *
     39 * @example
     40 * function addX( x ) {
     41 *     return function addY( y ) {
     42 *         return x + y;
     43 *     };
     44 * }
     45 *
     46 * var add = uncurry( addX );
     47 *
     48 * var sum = add( 2, 3 );
     49 * // returns 5
     50 */
     51 function uncurry( fcn, arity, thisArg ) {
     52 	var context;
     53 	var len;
     54 	if ( !isFunction( fcn ) ) {
     55 		throw new TypeError( 'invalid argument. First argument must be a function. Value: `'+fcn+'`.' );
     56 	}
     57 	if ( arguments.length < 2 ) {
     58 		len = null;
     59 	}
     60 	else if ( arguments.length > 2 ) {
     61 		len = arity;
     62 		context = thisArg;
     63 		if ( !isPositiveInteger( len ) ) {
     64 			throw new TypeError( 'invalid argument. Arity argument must be a positive integer. Value: `'+len+'`.' );
     65 		}
     66 	}
     67 	else if ( isPositiveInteger( arity ) ) {
     68 		len = arity;
     69 	}
     70 	else {
     71 		len = null;
     72 		context = arity;
     73 	}
     74 	return uncurried;
     75 
     76 	/**
     77 	* Uncurried function.
     78 	*
     79 	* @private
     80 	* @param {...*} args - arguments
     81 	* @throws {Error} if arity is set, must provide expected number of input arguments
     82 	* @throws {Error} configured arity must be compatible with curried function
     83 	* @throws {Error} if arity is not set, number of arguments must be compatible with curried function
     84 	* @returns {*} function result
     85 	*/
     86 	function uncurried() {
     87 		var f;
     88 		var i;
     89 
     90 		f = fcn;
     91 		if ( len ) {
     92 			if ( len > arguments.length ) {
     93 				throw new Error( 'insufficient input arguments. Expected '+len+' argument(s) and only received '+arguments.length+' argument(s).' );
     94 			}
     95 			for ( i = 0; i < len; i++ ) {
     96 				if ( isFunction( f ) ) {
     97 					f = f.call( context, arguments[ i ] );
     98 				} else {
     99 					throw new Error( 'invalid invocation. The configured arity exceeds the number of possible curried function invocations. Expected: '+len+'. Actual: '+i+'.' );
    100 				}
    101 			}
    102 			return f;
    103 		}
    104 		for ( i = 0; i < arguments.length; i++ ) {
    105 			if ( isFunction( f ) ) {
    106 				f = f.call( context, arguments[ i ] );
    107 			} else {
    108 				throw new Error( 'invalid invocation. Number of arguments exceeds the number of possible curried function invocations. Expected: '+arguments.length+'. Actual: '+i+'.' );
    109 			}
    110 		}
    111 		return f;
    112 	}
    113 }
    114 
    115 
    116 // EXPORTS //
    117 
    118 module.exports = uncurry;