lodash/slice.js at master · lodash/lodash

Cannot retrieve contributors at this time

47 lines (44 sloc) 1.21 KB

	/**
	* Creates a slice of `array` from `start` up to, but not including, `end`.
	*
	* Note: This method is used instead of
	* [`Array#slice`](https://mdn.io/Array/slice) to ensure dense arrays are
	* returned.
	*
	* @since 3.0.0
	* @category Array
	* @param {Array} array The array to slice.
	* @param {number} [start=0] The start position. A negative index will be treated as an offset from the end.
	* @param {number} [end=array.length] The end position. A negative index will be treated as an offset from the end.
	* @returns {Array} Returns the slice of `array`.
	* @example
	*
	* var array = [1, 2, 3, 4]
	*
	* _.slice(array, 2)
	* // => [3, 4]
	*/
	function slice(array, start, end) {
	let length = array == null ? 0 : array.length
	if (!length) {
	return []
	}
	start = start == null ? 0 : start
	end = end === undefined ? length : end

	if (start < 0) {
	start = -start > length ? 0 : (length + start)
	}
	end = end > length ? length : end
	if (end < 0) {
	end += length
	}
	length = start > end ? 0 : ((end - start) >>> 0)
	start >>>= 0

	let index = -1
	const result = new Array(length)
	while (++index < length) {
	result[index] = array[index + start]
	}
	return result
	}

	export default slice

lodash / lodash Public