Js Es6 Auto Currying

curry.js

/** cu - auto currying function
 * 
 * @param {function} fn  the function to autocurry
 * @param {integer} argc the number of args to autocurry if reflection is not possible
 */

function cu(fn, argc = null) {
  const len = argc || fn.length;

  const makeStack = (argsStack = []) => (...n) => {
    const args = argsStack.concat(n);
    if (args.length >= len) {
      return fn(...args);
    }
    return makeStack(args);
  };

  return makeStack()
}