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1571 :: Forward declaration and nested functions

• Henry (orginal) [2015-08-23T18:59:35+02:00] view original

  Should the following be possible in Nim as it is an Ada:

  proc a() =
    let i = 10
    
    proc c()
    
    proc b(doC: bool) =
      if doC:
        c()
    
    proc c() =
      echo($i)
      b(false)
    
    b(true)
  
  a()
  Run

  It appears there is a problem with b calling c and c calling b even thought there is a forward declaration for c. The Nim compiler is fine with the code but the generated C fails to compiles:

  nestTest.c: In function ‘c_92006’:
  /home/dm2/henry/Languages/Nimbol/nimcache/nestTest.c:314:37: error: ‘HEX3Aenv_92032’ undeclared (first use in this function)
    LOC2.ClPrc = b_92008; LOC2.ClEnv = HEX3Aenv_92032;

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• dom96 (orginal) [2015-08-23T19:27:34+02:00] view original

  I think it's a bug. Seems it's already been reported: https://github.com/nim-lang/Nim/issues/1807

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• Henry (orginal) [2015-08-23T19:38:33+02:00] view original

  Right, this is the same problem. I also tried marking the forward declaration as a closure but the error is the same.

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• bogen (orginal) [2015-08-28T05:37:53+02:00] view original

  Interesting. I tried several variations of this, declaring c as variable of type proc () prior to b, but no variation worked (the nim compiled, but not the C).

  The following is the only variation I got to work:

  proc a() =
    let i = 10
    
    proc b(doC: bool, c: proc()) =
      if doC:
        c()
    
    proc c() =
      echo($i)
      b(false, c)
    
    b(true, c)
  
  a()
  Run

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