multikeys

Multikeys is a TypeScript collection of trie‑based Map, Set, WeakMap, and WeakSet designed for high performance.

• ✨ TypeScript-first
• 🪶 Zero dependencies
• 🚀 Optimized trie-based implementation (see benchmarks)

Check API Reference.

Example of usage

const mkMap = new MKMap();

mkMap.set([1, 2, 3], "foo");
mkMap.set([3, 2, 1], "bar");

// order of keys matters
mkMap.get([1, 2, 3]); // => 'foo'
mkMap.get([3, 2, 1]); // => 'bar'

// an argument with empty keys is also valid
mkMap.set([], "zero");
mkMap.get([]); // => 'zero'
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const mkSet = new MKSet();
const obj = {};

mkSet.add([obj, 1]);
mkSet.has([{}, 1]); // => false, because {} is a new object, {} !== obj
mkSet.has([obj, 1]); // => true
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Using MKMap we could simply add memoization to function with a variable number of arguments:

const { MKMap } = require("multikeys");

function memoize(func) {
  const mkMap = new MKMap();

  return (...args) => {
    if (mkMap.has(args)) {
      return mkMap.get(args);
    }

    const res = func(...args);

    mkMap.set(args, res);

    return res;
  };
}
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Also, we could replace MKMap with MKWeakMap and get memoize with auto garbage collection. In such case only objects could be func arguments.