isNumber.js
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var isObjectLike = require('../internal/isObjectLike');
/** `Object#toString` result references. */
var numberTag = '[object Number]';
/** Used for native method references. */
var objectProto = Object.prototype;
/**
* Used to resolve the [`toStringTag`](http://ecma-international.org/ecma-262/6.0/#sec-object.prototype.tostring)
* of values.
*/
var objToString = objectProto.toString;
/**
* Checks if `value` is classified as a `Number` primitive or object.
*
* **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are classified
* as numbers, use the `_.isFinite` method.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isNumber(8.4);
* // => true
*
* _.isNumber(NaN);
* // => true
*
* _.isNumber('8.4');
* // => false
*/
function isNumber(value) {
return typeof value == 'number' || (isObjectLike(value) && objToString.call(value) == numberTag);
}
module.exports = isNumber;