JSFiddle - React, Tailwind, and code Playground

by Vladymyr Shevchuk

JavaScript

function sum (n) {
  function innerSum (value) {
    if (isFinite(value)) {
      innerSum.accum += value;
    }

    return innerSum;
  }

  innerSum.accum = 0;

  innerSum.toString = () => {
    return innerSum.accum;
  };

  return innerSum(n);
}

alert(+sum(1)(2)(3));