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4155 :: how to pass a class method as proc type param?or is there partial function in Nim ?

• bung (orginal) [2018-08-25T12:53:23+02:00] view original

  as title

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• LeuGim (orginal) [2018-08-25T16:15:47+02:00] view original

  You can use closures (or just intermediate procs w/o outer variables capturing) to bind specific method or specific overloaded procedure version and some arguments (partial evaluation):

  type
    Obj = ref object of RootObj
    Obj2 = ref object of Obj
  method m(x: Obj, n: int) {.base.} = echo "Obj " & $n
  method m(x: Obj2, n: int) = echo "Obj2 " & $n
  
  proc callTwice(x: Obj, p: proc(x: Obj)) = p x; p x
  
  var x: Obj
  x = new Obj2
  callTwice(x, proc(x: Obj) = m x, 7) # Obj2 7; Obj2 7
  Run

  For simple cases just use the routine's name to pass it:

  var y = new Obj
  proc p(x: Obj) = echo "p"
  y.p # => p
  callTwice y, p # => p; p
  Run

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• bung (orginal) [2018-08-25T17:54:56+02:00] view original

   nim
  proc callTwice( p: proc())
  Run

  what if param as p: proc(), how to pass the method

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• DeletedUser (orginal) [2018-08-25T19:59:00+02:00] view original

  You can't, you have to wrap it in a closure.

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• bung (orginal) [2018-08-25T21:40:26+02:00] view original

  then that's a proc(){.closure.} type, will not pass compile

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• LeuGim (orginal) [2018-08-25T22:48:57+02:00] view original

  You can try to provide a full example of what you want to achieve.

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• bung (orginal) [2018-08-26T03:02:42+02:00] view original

  https://github.com/bung87/daemon/blob/fb0099dbb8b1927a9d4cc259323d1b9d4124e470/src/daemonim.nim#L140

  the commented line I was trying to , and now I using generic proc ,store param global, since I tried many time...

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