Generate all combinations of provided element set

permute.js

function* permute(permutation) {
	let length = permutation.length;
	let c = Array(length).fill(0);
	let i = 1;
	let k;
	let p;
	yield permutation;
	
	while (i < length) {
		if (c[i] < i) {
			k = i % 2 && c[i];
			p = permutation[i];
			permutation[i] = permutation[k];
			permutation[k] = p;
			++c[i];
			i = 1;
			yield permutation;
		}
		else {
			c[i] = 0;
			++i;
		}
	}
}