time-to-botec

Benchmark sampling in different programming languages
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main.js (2954B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2020 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 setReadOnly = require( '@stdlib/utils/define-nonenumerable-read-only-property' );
     24 var iteratorSymbol = require( '@stdlib/symbol/iterator' );
     25 var factorial = require( './../../../../base/special/factorial' );
     26 var validate = require( './validate.js' );
     27 
     28 
     29 // VARIABLES //
     30 
     31 var MAX_ITER = 1e308;
     32 
     33 
     34 // MAIN //
     35 
     36 /**
     37 * Returns an iterator which generates a sequence of factorials.
     38 *
     39 * ## Notes
     40 *
     41 * -   If an environment supports `Symbol.iterator`, the returned iterator is iterable.
     42 *
     43 * @param {Options} [options] - function options
     44 * @param {NonNegativeInteger} [options.iter=1e308] - number of iterations
     45 * @throws {TypeError} options argument must be an object
     46 * @throws {TypeError} must provide valid options
     47 * @returns {Iterator} iterator
     48 *
     49 * @example
     50 * var iter = iterFactorialsSeq();
     51 *
     52 * var v = iter.next().value;
     53 * // returns 1
     54 *
     55 * v = iter.next().value;
     56 * // returns 1
     57 *
     58 * v = iter.next().value;
     59 * // returns 2
     60 *
     61 * // ...
     62 */
     63 function iterFactorialsSeq( options ) {
     64 	var opts;
     65 	var iter;
     66 	var FLG;
     67 	var err;
     68 	var i;
     69 
     70 	opts = {
     71 		'iter': MAX_ITER
     72 	};
     73 	if ( arguments.length ) {
     74 		err = validate( opts, options );
     75 		if ( err ) {
     76 			throw err;
     77 		}
     78 	}
     79 	i = -1;
     80 
     81 	// Create an iterator protocol-compliant object:
     82 	iter = {};
     83 	setReadOnly( iter, 'next', next );
     84 	setReadOnly( iter, 'return', end );
     85 
     86 	// If an environment supports `Symbol.iterator`, make the iterator iterable:
     87 	if ( iteratorSymbol ) {
     88 		setReadOnly( iter, iteratorSymbol, factory );
     89 	}
     90 	return iter;
     91 
     92 	/**
     93 	* Returns an iterator protocol-compliant object containing the next iterated value.
     94 	*
     95 	* @private
     96 	* @returns {Object} iterator protocol-compliant object
     97 	*/
     98 	function next() {
     99 		i += 1;
    100 		if ( FLG || i >= opts.iter ) {
    101 			return {
    102 				'done': true
    103 			};
    104 		}
    105 		return {
    106 			'value': factorial( i ),
    107 			'done': false
    108 		};
    109 	}
    110 
    111 	/**
    112 	* Finishes an iterator.
    113 	*
    114 	* @private
    115 	* @param {*} [value] - value to return
    116 	* @returns {Object} iterator protocol-compliant object
    117 	*/
    118 	function end( value ) {
    119 		FLG = true;
    120 		if ( arguments.length ) {
    121 			return {
    122 				'value': value,
    123 				'done': true
    124 			};
    125 		}
    126 		return {
    127 			'done': true
    128 		};
    129 	}
    130 
    131 	/**
    132 	* Returns a new iterator.
    133 	*
    134 	* @private
    135 	* @returns {Iterator} iterator
    136 	*/
    137 	function factory() {
    138 		return iterFactorialsSeq( opts );
    139 	}
    140 }
    141 
    142 
    143 // EXPORTS //
    144 
    145 module.exports = iterFactorialsSeq;