nhb-toolbox/dist/esm/string/anagram.js

A versatile collection of smart, efficient, and reusable utility functions, classes and types for everyday development needs.

import { isValidArray } from '../guards/non-primitives.js';
import { isNonEmptyString } from '../guards/primitives.js';
const DICT_CACHE = new WeakMap();
function _getDictSet(dict) {
    if (DICT_CACHE.has(dict))
        return DICT_CACHE.get(dict);
    const dictSet = new Set(dict.map((w) => w.toLowerCase()));
    DICT_CACHE.set(dict, dictSet);
    return dictSet;
}
export function generateAnagrams(word, options) {
    if (!isNonEmptyString(word))
        return [];
    if (word?.length === 1)
        return [word?.toLowerCase()];
    const { limit = 100, dictionary = false } = options || {};
    const outSet = new Set();
    const dictSet = isValidArray(dictionary) ? _getDictSet(dictionary) : undefined;
    const _permute = (current, remaining) => {
        if (!remaining.length) {
            if (!dictSet || dictSet.has(current)) {
                outSet.add(current);
            }
            return;
        }
        const usedSet = new Set();
        for (let i = 0; i < remaining.length; i++) {
            const char = remaining[i];
            if (usedSet.has(char))
                continue;
            usedSet.add(char);
            if (limit !== 'all' && outSet.size >= limit)
                return;
            _permute(current + char, remaining.slice(0, i) + remaining.slice(i + 1));
        }
    };
    _permute('', word.toLowerCase());
    return [...outSet];
}