Function _unique

external/.datatables.js:1287–1321

(src)

	 * @ignore
	 */
	var _unique = function (src) {
		if (Array.from && Set) {
			return Array.from(new Set(src))
		}

		if (_areAllUnique(src)) {
			return src.slice()
		}

		// A faster unique method is to use object keys to identify used values,
		// but this doesn't work with arrays or objects, which we must also
		// consider. See jsperf.app/compare-array-unique-versions/4 for more
		// information.
		var out = [],
			val,
			i,
			ien = src.length,
			j,
			k = 0

		again: for (i = 0; i < ien; i++) {
			val = src[i]

			for (j = 0; j < k; j++) {
				if (out[j] === val) {
					continue again
				}
			}

			out.push(val)
			k++
		}

		return out
	}

	// Surprisingly this is faster than [].concat.apply
	// https://jsperf.com/flatten-an-array-loop-vs-reduce/2