Lists all possible subsequences.
Similar: subsequence, subsequences, hasSubsequence, searchSubsequence.
This is part of package extra-array.
array.subsequences(x, [n]);
// x: an array
// n: number of values (-1 => any)const array = require("extra-array");
[...array.subsequences([1, 2])];
// [ [], [ 1 ], [ 2 ], [ 1, 2 ] ]
[...array.subsequences([1, 2, 3])];
// [
// [], [ 1 ],
// [ 2 ], [ 1, 2 ],
// [ 3 ], [ 1, 3 ],
// [ 2, 3 ], [ 1, 2, 3 ]
// ]