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- /** Used as references for various `Number` constants. */
- var MAX_SAFE_INTEGER = 9007199254740991;
- /** Used to detect unsigned integer values. */
- var reIsUint = /^(?:0|[1-9]\d*)$/;
- /**
- * Checks if `value` is a valid array-like index.
- *
- * @private
- * @param {*} value The value to check.
- * @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index.
- * @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
- */
- function isIndex(value, length) {
- value = (typeof value == 'number' || reIsUint.test(value)) ? +value : -1;
- length = length == null ? MAX_SAFE_INTEGER : length;
- return value > -1 && value % 1 == 0 && value < length;
- }
- export default isIndex;
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