DefectingCat/sum.js

Last active: 2 years ago

Sum with an arbitray amount of brackets

sum.js

function sum(a) {
  let currentSum = a;

  function f(b) {
    currentSum += b;
    return f;
  }

  f.toString = function () {
    return currentSum;
  };
  f[Symbol.toPrimitive] = function () {
    return currentSum;
  };

  return f;
}

console.log(sum(1)(2).toString());

sum_without_function.js

function sum(a) {
  sum.current = (sum.current ?? 0) + a;
  sum.toString = () => sum.current;
  return sum;
}

console.log(sum(1)(2).toString());

sum_without_variable.js

function sum(a) {

  function f(b) {
    return sum(a + b);
  }

  f.toString = () => a

  return f;
}

console.log(sum(1)(2).toString());