Generic params will not match for void type

[fowlmouth]

In the bottom example for squaz curry doesn't match without the special-cased curry()

proc curry[A, Ret] (
    funk: proc(someA: A): Ret, 
    valueA: A): proc: Ret =
  return proc: Ret = funk(valueA)
proc curry[A,B, Ret] (
    funk: proc(someA: A, someB: B): Ret, 
    valueA: A): proc(someB: B): Ret =
  return proc(someB: B): Ret = funk(valueA, someB)
proc curry[A,B,C, Ret] (
    funk: proc(someA: A, someB: B, someC: C): Ret,
    valueA: A): proc(someB: B, someC: C): Ret =
  return proc(someB: B, someC: C): Ret = funk(valueA, someB, someC)
proc curry[A,B,C,D, Ret] (
    funk: proc(someA:A, someB:B, someC:C, someD:D): Ret,
    valueA: A): proc(someB:B,someC:C,someD:D): Ret =
  return proc(someB:B,someC:C,someD:D): Ret = funk(valueA, someB,someC,someD)


when isMainModule:
  proc foo(a, b: int): int =
    return a * b

  proc foo2(a, b, c: int): int =
    return a * b * c

  let f = foo.curry(50)
  assert f(2) == 100

  let f2 = foo2.curry(2)
  assert f2(3, 2) == 12
  assert f2.curry(3)(2) == 12

  proc squaz(some: int) = echo(some)


  curry[int,void](squaz, 9001)()
  proc curry[A] (funk: proc(someA: A), valueA: A): proc() =
    return proc = funk(valueA)
  ## this doesnt work without the above function
  curry(squaz, 9001)()

[Araq]

Works as intended; however seems easy to support.

[zah]

I think the language is not complete until we can define curry in a single line :)

Ideally, it should take (f: proc, args: varargs[expr]) parameters and it should use some magic
from the typetraits module to get the arity of the passed proc, which combined with the number of
varargs is enough to generate the proper body of the returned closure.

[despairblue]

👍

[fowlmouth]

Curry is much better in 2015
https://gist.github.com/fowlmouth/9b9010397ad5fe4b9872#file-xcurry-nim
this uses the new compile time type api

[dom96]

@fowlmouth That is very nice. Candidate for the future module? (perhaps the future module should be known as fputils or something relating to functional programming).

[Araq]

Instead void should be tweaked.