Simple currying example in JS

curry.js

class Curry {
  constructor(fn) {
    return this.curry(fn, fn.length, [])
  }
  
  curry(fn, argRestCounter, args) {
    if (argRestCounter === 0) return fn(…args);
    return arg => this.curry(fn, argRestCounter — 1, […args, arg]);
  }
}

const f = (x, y, z) => x * y + z;
const cur = new Curry(f);
cur(2)(3)(4) // 10