curried_sum.js

const soma = n => {
  sum = n
  const proxy = new Proxy(() => {}, {
    get(obj, key) {
      return () => {
        if (sum) return sum
      }
    },

    apply(receiver, ...args) {
      if (args[1][0])
        sum += args[1][0]
      else
        sum += 0

      return proxy
    },
  })

  return proxy
}


console.log(soma(1)(2)(3)(5)(4)(10)(20)) // 45
console.log(soma(1)(1)(1)(1)(1)(1))      // 6
console.log(soma(1)(1)(1)(1)(1)()(1))    // 6