aaac7fed
 liuqimichale
add
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/** Used as references for various `Number` constants. */
var MAX_SAFE_INTEGER = 9007199254740991;
/**
* Checks if `value` is a valid array-like length.
*
* **Note:** This method is loosely based on
* [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
*
* @static
* @memberOf _
* @since 4.0.0
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
* @example
*
* _.isLength(3);
* // => true
*
* _.isLength(Number.MIN_VALUE);
* // => false
*
* _.isLength(Infinity);
* // => false
*
* _.isLength('3');
* // => false
*/
function isLength(value) {
return typeof value == 'number' &&
value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
}
module.exports = isLength;
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