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13475 :: Enum types

• sonicsmooth (orginal) [2025-10-25T20:32:02+02:00] view original

  Is it possible to make an enum a specific type?

  I saw a {.magic: int32.} somewhere but that didn't do the trick.

  I'm trying to avoid adding .UINT or .int32 when used with Win32 functions.

  For example (using wNim specifically)

  type UserIDs* = enum idMouseMove = WM_USER, idSize, idSlider, idAlgUpdate

  Thanks

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• Araq (orginal) [2025-10-25T22:33:38+02:00] view original

  Like this:

  
  type UserIDs* {.size: 4.} = enum
    idMouseMove = WM_USER, idSize, idSlider, idAlgUpdate
  Run

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• sonicsmooth (orginal) [2025-10-26T05:55:38+01:00] view original

  Thanks, that works for setting the size, but the SendMessage(...) proc still wants the arg to be a .UINT.

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• darkestpigeon (orginal) [2025-10-26T16:52:50+01:00] view original

  What are you trying to do exactly?

  If you're binding a C function, you can declare its signature to use your enum

  
  void do_stuff(uint32_t x) { printf("%d\n", x); }
  Run

  
  
  type MyEnum {.size: 4.} = enum
    aaa = 13
    bbb
    ccc
  
  proc doStuffFromC(x: MyEnum) {.importc: "do_stuff".}
  
  doStuffFromC(aaa)
  Run

  If you want to call procs that take uint32 with your enum without adding .uint32 every time, you can define a converter

  
  type MyEnum = enum
    aaa = 13
    bbb
    ccc
  
  converter toUint32(x: MyEnum): uint32 = x.uint32
  
  proc doStuff(x: uint32) = echo x
  
  doStuff(aaa)
  Run

  Just make sure converter symbol is visible.

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