time-to-botec

Benchmark sampling in different programming languages
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main.js (3131B)

      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 FLOAT64_MAX_SAFE_INTEGER = require( '@stdlib/constants/float64/max-safe-integer' );
     26 var validate = require( './validate.js' );
     27 
     28 
     29 // VARIABLES //
     30 
     31 var MAX_ITER = ((FLOAT64_MAX_SAFE_INTEGER+1) / 2) + 1;
     32 
     33 
     34 // MAIN //
     35 
     36 /**
     37 * Returns an iterator which generates a sequence of nonnegative even integers.
     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=4503599627370497] - 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 = iterNonNegativeEvenIntegersSeq();
     51 *
     52 * var v = iter.next().value;
     53 * // returns 0
     54 *
     55 * v = iter.next().value;
     56 * // returns 2
     57 *
     58 * v = iter.next().value;
     59 * // returns 4
     60 *
     61 * // ...
     62 */
     63 function iterNonNegativeEvenIntegersSeq( options ) { // eslint-disable-line id-length
     64 	var opts;
     65 	var iter;
     66 	var FLG;
     67 	var err;
     68 	var i;
     69 	var j;
     70 
     71 	opts = {
     72 		'iter': MAX_ITER
     73 	};
     74 	if ( arguments.length ) {
     75 		err = validate( opts, options );
     76 		if ( err ) {
     77 			throw err;
     78 		}
     79 	}
     80 	i = 0;
     81 	j = -2;
     82 
     83 	// Create an iterator protocol-compliant object:
     84 	iter = {};
     85 	setReadOnly( iter, 'next', next );
     86 	setReadOnly( iter, 'return', end );
     87 
     88 	// If an environment supports `Symbol.iterator`, make the iterator iterable:
     89 	if ( iteratorSymbol ) {
     90 		setReadOnly( iter, iteratorSymbol, factory );
     91 	}
     92 	return iter;
     93 
     94 	/**
     95 	* Returns an iterator protocol-compliant object containing the next iterated value.
     96 	*
     97 	* @private
     98 	* @returns {Object} iterator protocol-compliant object
     99 	*/
    100 	function next() {
    101 		i += 1;
    102 		if ( FLG || i > opts.iter ) {
    103 			return {
    104 				'done': true
    105 			};
    106 		}
    107 		j += 2;
    108 		return {
    109 			'value': j,
    110 			'done': false
    111 		};
    112 	}
    113 
    114 	/**
    115 	* Finishes an iterator.
    116 	*
    117 	* @private
    118 	* @param {*} [value] - value to return
    119 	* @returns {Object} iterator protocol-compliant object
    120 	*/
    121 	function end( value ) {
    122 		FLG = true;
    123 		if ( arguments.length ) {
    124 			return {
    125 				'value': value,
    126 				'done': true
    127 			};
    128 		}
    129 		return {
    130 			'done': true
    131 		};
    132 	}
    133 
    134 	/**
    135 	* Returns a new iterator.
    136 	*
    137 	* @private
    138 	* @returns {Iterator} iterator
    139 	*/
    140 	function factory() {
    141 		return iterNonNegativeEvenIntegersSeq( opts );
    142 	}
    143 }
    144 
    145 
    146 // EXPORTS //
    147 
    148 module.exports = iterNonNegativeEvenIntegersSeq;