@zsnout/ithkuil/generate/helpers/permutations.js

A set of tools which can generate and parse romanized Ithkuil text and which can generate Ithkuil script from text and JSON data.

// https://stackoverflow.com/a/37580979/17763661
export function allPermutationsOf(array) {
    const permutation = array.slice();
    const length = permutation.length;
    const result = [permutation.slice()];
    const c = new Array(length).fill(0);
    let i = 1;
    let k, p;
    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;
            result.push(permutation.slice());
        }
        else {
            c[i] = 0;
            ++i;
        }
    }
    return result;
}