time-to-botec

Benchmark sampling in different programming languages
Log | Files | Refs | README

until_each_right.js (2903B)

      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 isCollection = require( '@stdlib/assert/is-collection' );
     24 var isFunction = require( '@stdlib/assert/is-function' );
     25 
     26 
     27 // MAIN //
     28 
     29 /**
     30 * Until a test condition is true, invokes a function once for each element in a collection, iterating from right to left.
     31 *
     32 * ## Notes
     33 *
     34 * -   For dynamic array resizing, the only behavior made intentionally consistent with `untilEach` (iterating from left to right) is when elements are pushed onto the beginning (end) of an array. In other words, for `untilEach()`, `[].push()` behavior is consistent with `untilEachRight()` `[].unshift()` behavior.
     35 *
     36 *
     37 * @param {Collection} collection - input collection
     38 * @param {Function} predicate - function which indicates whether to stop iterating over a collection
     39 * @param {Function} fcn - function to invoke
     40 * @param {*} [thisArg] - execution context for the applied function
     41 * @throws {TypeError} first argument must be a collection
     42 * @throws {TypeError} second argument must be a function
     43 * @throws {TypeError} third argument must be a function
     44 * @returns {Collection} input collection
     45 *
     46 * @example
     47 * function predicate( v, index, collection ) {
     48 *     return ( v !== v );
     49 * }
     50 *
     51 * function log( v, index, collection ) {
     52 *     console.log( '%s: %d', index, v );
     53 * }
     54 *
     55 * var arr = [ 1, NaN, 2, 3, 4, 5 ];
     56 *
     57 * untilEachRight( arr, predicate, log );
     58 */
     59 function untilEachRight( collection, predicate, fcn, thisArg ) {
     60 	var len;
     61 	var i;
     62 	if ( !isCollection( collection ) ) {
     63 		throw new TypeError( 'invalid argument. First argument must be a collection. Value: `'+collection+'`.' );
     64 	}
     65 	if ( !isFunction( predicate ) ) {
     66 		throw new TypeError( 'invalid argument. Second argument must be a function. Value: `'+predicate+'`.' );
     67 	}
     68 	if ( !isFunction( fcn ) ) {
     69 		throw new TypeError( 'invalid argument. Third argument must be a function. Value: `'+fcn+'`.' );
     70 	}
     71 	len = collection.length;
     72 	i = len - 1;
     73 	while (
     74 		i >= 0 &&
     75 		!predicate( collection[ i ], i, collection )
     76 	) {
     77 		fcn.call( thisArg, collection[ i ], i, collection );
     78 
     79 		// Account for dynamically resizing a collection...
     80 		if ( len !== collection.length ) {
     81 			i += ( collection.length - len );
     82 			len = collection.length;
     83 		}
     84 		i -= 1;
     85 	}
     86 	return collection;
     87 }
     88 
     89 
     90 // EXPORTS //
     91 
     92 module.exports = untilEachRight;