Variadic curried sum function

Question

I need a js sum function to work like this:

sum(1)(2) = 3
sum(1)(2)(3) = 6
sum(1)(2)(3)(4) = 10 
etc.

I heard it can\'t be done. But heard

Answer 1

Try this

function sum (...args) {
  return Object.assign(
    sum.bind(null, ...args),
    { valueOf: () => args.reduce((a, c) => a + c, 0) }
  )
}

console.log(+sum(1)(2)(3,2,1)(16))

Here you can see a medium post about carried functions with unlimited arguments

https://medium.com/@seenarowhani95/infinite-currying-in-javascript-38400827e581