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1509 :: help understanding closure oddness

• ggibson (orginal) [2015-08-10T01:44:47+02:00] view original

  2 Questions:

  1. How can I call a closure from a closure?
  2. Why must proc references be closures if stored in an array, but not if stored in single variable references?

  
  proc functional1(x,y:int):int {.closure.} =
     return x+y
  
  proc functional2(x,y:int):int {.closure.} =
     result = functional1(x,y) ## breaks
     #result = 0 ## doing this instead, works
  
  type
     ordinal {.pure.} = enum one, two
  
  let fns = array[ordinal, proc(x,y:int):int]([functional1, functional2])
  echo fns[ordinal.one](3, 5)
  Run

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• Varriount (orginal) [2015-08-10T03:25:57+02:00] view original

  The error you get is a bug, and should probably be reported on the issue tracker (if it isn't already).

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• dom96 (orginal) [2015-08-10T08:34:15+02:00] view original

  Remove the closure pragma from those procedures. It should work. Top level statements can never be closures.

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• Araq (orginal) [2015-08-10T09:27:11+02:00] view original

  Use this:

  proc functional1(x,y:int):int =
     return x+y
  
  proc functional2(x,y:int):int =
     result = functional1(x,y)
  
  let fns = array[ordinal, proc(x,y:int):int {.nimcall.}]([functional1, functional2])
  Run

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• ggibson (orginal) [2015-08-10T15:10:22+02:00] view original

  Awesome; thank you. I was confused because nimcall is the default type in all other proc situations I've encountered.

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