time-to-botec

Benchmark sampling in different programming languages
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some_by.js (2526B)

      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 isPositiveInteger = require( '@stdlib/assert/is-positive-integer' ).isPrimitive;
     25 var isFunction = require( '@stdlib/assert/is-function' );
     26 
     27 
     28 // MAIN //
     29 
     30 /**
     31 * Tests whether a collection contains at least `n` elements which pass a test implemented by a predicate function.
     32 *
     33 * @param {Collection} collection - input collection
     34 * @param {PositiveInteger} n - number of elements
     35 * @param {Function} predicate - test function
     36 * @param {*} [thisArg] - execution context
     37 * @throws {TypeError} first argument must be a collection
     38 * @throws {TypeError} second argument must be a positive integer
     39 * @throws {TypeError} third argument must be a function
     40 * @returns {boolean} boolean indicating whether a collection contains at least `n` elements which pass a test
     41 *
     42 * @example
     43 * function isNegative( v ) {
     44 *     return ( v < 0 );
     45 * }
     46 *
     47 * var arr = [ 1, 2, -3, 4, -1 ];
     48 *
     49 * var bool = someBy( arr, 2, isNegative );
     50 * // returns true
     51 */
     52 function someBy( collection, n, predicate, thisArg ) {
     53 	var count;
     54 	var out;
     55 	var len;
     56 	var i;
     57 	if ( !isCollection( collection ) ) {
     58 		throw new TypeError( 'invalid argument. First argument must be a collection. Value: `'+collection+'`.' );
     59 	}
     60 	if ( !isPositiveInteger( n ) ) {
     61 		throw new TypeError( 'invalid argument. Second argument must be a positive integer. Value: `'+n+'`.' );
     62 	}
     63 	if ( !isFunction( predicate ) ) {
     64 		throw new TypeError( 'invalid argument. Third argument must be a function. Value: `'+predicate+'`.' );
     65 	}
     66 	len = collection.length;
     67 	count = 0;
     68 	for ( i = 0; i < len; i++ ) {
     69 		out = predicate.call( thisArg, collection[ i ], i, collection );
     70 		if ( out ) {
     71 			count += 1;
     72 			if ( count === n ) {
     73 				return true;
     74 			}
     75 		}
     76 		// Account for dynamically resizing a collection:
     77 		len = collection.length;
     78 	}
     79 	return false;
     80 }
     81 
     82 
     83 // EXPORTS //
     84 
     85 module.exports = someBy;