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7688 :: auto declaration of function prototype

• jseb (orginal) [2021-03-23T15:59:26+01:00] view original

  Hello,

  This kind of code needs function prototyping.

  proc a()
  proc b()
  
  proc a() =
    echo "a"
    b()
  
  proc b() =
    echo "b"
  Run

  Is it possible to auto-declare the procedures ? May be with a macro, for generating the beginning (but should parse the entire AST for finding functions ?):

  proc a()
  proc b()
  Run

  Thank you.

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• exelotl (orginal) [2021-03-23T18:49:19+01:00] view original

  The experimental codeReordering feature is probably what you're looking for :)

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• Araq (orginal) [2021-03-23T20:23:25+01:00] view original

  I suspect it's on the list of things to be revisited and formalised after incremental compilation lands?

  Exactly.

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• jseb (orginal) [2021-03-24T11:27:57+01:00] view original

  thank you for the answer.

  {.codeReordering.} is interesting for usual cases, but mine looks like this:

  type RGB = enum r,g,b
  
  #proc pr()
  #proc pg()
  #proc pb()
  
  var fx = [ r:pr, g:pg, b:pb ]
  
  var currfx = fx[r]
  
  proc pr() =
    currfx = fx[g]
    echo "red will be green next time"
  proc pg() =
    currfx = fx[b]
    echo "green will be blue next time"
  proc pb() =
    currfx = fx[r]
    echo "blue will be red next time"
  
  currfx()
  currfx()
  currfx()
  Run

  so i believe i will have to keep prototyping or find a way to do it with either:

  • the Makefile, by generating functions prototypes in a file, inserted at the beginning of the nim source code (quite easy but ugly).
  • with macros, which could be a good way to learn to use them.

  Guess what, for the moment i think i stick to the old fashioned prototyping :)

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