1  /**
  2   * lodash (Custom Build) <https://lodash.com/>
  3   * Build: `lodash modularize exports="npm" -o ./`
  4   * Copyright jQuery Foundation and other contributors <https://jquery.org/>
  5   * Released under MIT license <https://lodash.com/license>
  6   * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
  7   * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
  8   */
  9  
 10  /** Used as references for various `Number` constants. */
 11  var INFINITY = 1 / 0,
 12      MAX_INTEGER = 1.7976931348623157e+308,
 13      NAN = 0 / 0;
 14  
 15  /** `Object#toString` result references. */
 16  var symbolTag = '[object Symbol]';
 17  
 18  /** Used to match leading and trailing whitespace. */
 19  var reTrim = /^\s+|\s+$/g;
 20  
 21  /** Used to detect bad signed hexadecimal string values. */
 22  var reIsBadHex = /^[-+]0x[0-9a-f]+$/i;
 23  
 24  /** Used to detect binary string values. */
 25  var reIsBinary = /^0b[01]+$/i;
 26  
 27  /** Used to detect octal string values. */
 28  var reIsOctal = /^0o[0-7]+$/i;
 29  
 30  /** Built-in method references without a dependency on `root`. */
 31  var freeParseInt = parseInt;
 32  
 33  /** Used for built-in method references. */
 34  var objectProto = Object.prototype;
 35  
 36  /**
 37   * Used to resolve the
 38   * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
 39   * of values.
 40   */
 41  var objectToString = objectProto.toString;
 42  
 43  /**
 44   * Checks if `value` is an integer.
 45   *
 46   * **Note:** This method is based on
 47   * [`Number.isInteger`](https://mdn.io/Number/isInteger).
 48   *
 49   * @static
 50   * @memberOf _
 51   * @since 4.0.0
 52   * @category Lang
 53   * @param {*} value The value to check.
 54   * @returns {boolean} Returns `true` if `value` is an integer, else `false`.
 55   * @example
 56   *
 57   * _.isInteger(3);
 58   * // => true
 59   *
 60   * _.isInteger(Number.MIN_VALUE);
 61   * // => false
 62   *
 63   * _.isInteger(Infinity);
 64   * // => false
 65   *
 66   * _.isInteger('3');
 67   * // => false
 68   */
 69  function isInteger(value) {
 70    return typeof value == 'number' && value == toInteger(value);
 71  }
 72  
 73  /**
 74   * Checks if `value` is the
 75   * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types)
 76   * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
 77   *
 78   * @static
 79   * @memberOf _
 80   * @since 0.1.0
 81   * @category Lang
 82   * @param {*} value The value to check.
 83   * @returns {boolean} Returns `true` if `value` is an object, else `false`.
 84   * @example
 85   *
 86   * _.isObject({});
 87   * // => true
 88   *
 89   * _.isObject([1, 2, 3]);
 90   * // => true
 91   *
 92   * _.isObject(_.noop);
 93   * // => true
 94   *
 95   * _.isObject(null);
 96   * // => false
 97   */
 98  function isObject(value) {
 99    var type = typeof value;
100    return !!value && (type == 'object' || type == 'function');
101  }
102  
103  /**
104   * Checks if `value` is object-like. A value is object-like if it's not `null`
105   * and has a `typeof` result of "object".
106   *
107   * @static
108   * @memberOf _
109   * @since 4.0.0
110   * @category Lang
111   * @param {*} value The value to check.
112   * @returns {boolean} Returns `true` if `value` is object-like, else `false`.
113   * @example
114   *
115   * _.isObjectLike({});
116   * // => true
117   *
118   * _.isObjectLike([1, 2, 3]);
119   * // => true
120   *
121   * _.isObjectLike(_.noop);
122   * // => false
123   *
124   * _.isObjectLike(null);
125   * // => false
126   */
127  function isObjectLike(value) {
128    return !!value && typeof value == 'object';
129  }
130  
131  /**
132   * Checks if `value` is classified as a `Symbol` primitive or object.
133   *
134   * @static
135   * @memberOf _
136   * @since 4.0.0
137   * @category Lang
138   * @param {*} value The value to check.
139   * @returns {boolean} Returns `true` if `value` is a symbol, else `false`.
140   * @example
141   *
142   * _.isSymbol(Symbol.iterator);
143   * // => true
144   *
145   * _.isSymbol('abc');
146   * // => false
147   */
148  function isSymbol(value) {
149    return typeof value == 'symbol' ||
150      (isObjectLike(value) && objectToString.call(value) == symbolTag);
151  }
152  
153  /**
154   * Converts `value` to a finite number.
155   *
156   * @static
157   * @memberOf _
158   * @since 4.12.0
159   * @category Lang
160   * @param {*} value The value to convert.
161   * @returns {number} Returns the converted number.
162   * @example
163   *
164   * _.toFinite(3.2);
165   * // => 3.2
166   *
167   * _.toFinite(Number.MIN_VALUE);
168   * // => 5e-324
169   *
170   * _.toFinite(Infinity);
171   * // => 1.7976931348623157e+308
172   *
173   * _.toFinite('3.2');
174   * // => 3.2
175   */
176  function toFinite(value) {
177    if (!value) {
178      return value === 0 ? value : 0;
179    }
180    value = toNumber(value);
181    if (value === INFINITY || value === -INFINITY) {
182      var sign = (value < 0 ? -1 : 1);
183      return sign * MAX_INTEGER;
184    }
185    return value === value ? value : 0;
186  }
187  
188  /**
189   * Converts `value` to an integer.
190   *
191   * **Note:** This method is loosely based on
192   * [`ToInteger`](http://www.ecma-international.org/ecma-262/7.0/#sec-tointeger).
193   *
194   * @static
195   * @memberOf _
196   * @since 4.0.0
197   * @category Lang
198   * @param {*} value The value to convert.
199   * @returns {number} Returns the converted integer.
200   * @example
201   *
202   * _.toInteger(3.2);
203   * // => 3
204   *
205   * _.toInteger(Number.MIN_VALUE);
206   * // => 0
207   *
208   * _.toInteger(Infinity);
209   * // => 1.7976931348623157e+308
210   *
211   * _.toInteger('3.2');
212   * // => 3
213   */
214  function toInteger(value) {
215    var result = toFinite(value),
216        remainder = result % 1;
217  
218    return result === result ? (remainder ? result - remainder : result) : 0;
219  }
220  
221  /**
222   * Converts `value` to a number.
223   *
224   * @static
225   * @memberOf _
226   * @since 4.0.0
227   * @category Lang
228   * @param {*} value The value to process.
229   * @returns {number} Returns the number.
230   * @example
231   *
232   * _.toNumber(3.2);
233   * // => 3.2
234   *
235   * _.toNumber(Number.MIN_VALUE);
236   * // => 5e-324
237   *
238   * _.toNumber(Infinity);
239   * // => Infinity
240   *
241   * _.toNumber('3.2');
242   * // => 3.2
243   */
244  function toNumber(value) {
245    if (typeof value == 'number') {
246      return value;
247    }
248    if (isSymbol(value)) {
249      return NAN;
250    }
251    if (isObject(value)) {
252      var other = typeof value.valueOf == 'function' ? value.valueOf() : value;
253      value = isObject(other) ? (other + '') : other;
254    }
255    if (typeof value != 'string') {
256      return value === 0 ? value : +value;
257    }
258    value = value.replace(reTrim, '');
259    var isBinary = reIsBinary.test(value);
260    return (isBinary || reIsOctal.test(value))
261      ? freeParseInt(value.slice(2), isBinary ? 2 : 8)
262      : (reIsBadHex.test(value) ? NAN : +value);
263  }
264  
265  module.exports = isInteger;