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