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274 :: var or ptr for wrapping c

• enurlyx (orginal) [2013-10-12T20:32:32+02:00] view original

  I thought of using a ptr type when a c wrapperfunction needs a pointer. But i saw in windows.nim that var is used instead. So is it correct to use var instead of ptr?

  
  proc DrawFocusRect*(hDC: HDC, lprc: var RECT): WINBOOL{.stdcall,
      dynlib: "user32", importc: "DrawFocusRect".}
  
  proc DrawFocusRect*(hDC: HDC, lprc: ptr RECT): WINBOOL{.stdcall,
      dynlib: "user32", importc: "DrawFocusRect".}
  Run

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• Araq (orginal) [2013-10-12T22:58:56+02:00] view original

  Yes, it is correct to use 'var' instead.

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• leledumbo (orginal) [2013-10-13T07:28:32+02:00] view original

  Aren't both the same? It will just matter the way the parameter is passed by the caller code (except you can pass nil with ptr)

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