is_safe_integer.js (1459B)
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 MAX_SAFE_INTEGER = require( '@stdlib/constants/float64/max-safe-integer' ); 24 var MIN_SAFE_INTEGER = require( '@stdlib/constants/float64/min-safe-integer' ); 25 var isInteger = require( './../../../../base/assert/is-integer' ); 26 27 28 // MAIN // 29 30 /** 31 * Tests if a finite double-precision floating-point number is a safe integer. 32 * 33 * @param {number} x - value to test 34 * @returns {boolean} boolean indicating whether the value is a safe integer 35 * 36 * @example 37 * var bool = isSafeInteger( 1.0 ); 38 * // returns true 39 * 40 * @example 41 * var bool = isSafeInteger( 2.0e200 ); 42 * // returns false 43 * 44 * @example 45 * var bool = isSafeInteger( 3.14 ); 46 * // returns false 47 */ 48 function isSafeInteger( x ) { 49 return ( 50 x >= MIN_SAFE_INTEGER && 51 x <= MAX_SAFE_INTEGER && 52 isInteger( x ) 53 ); 54 } 55 56 57 // EXPORTS // 58 59 module.exports = isSafeInteger;