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_WinAPI_GetWindowLong Runtime Error

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Experiencing a run time error when running _WinAPI_GetWindowLong(). I've narrowed down my code to this code splice.

#include <WinAPI.au3>
#include <GUIConstantsEx.au3>
#include <WinAPI.au3>
#include <WindowsConstants.au3>


; Error at this line "Variable used without being declared"
$wstyle = _WinAPI_GetWindowLong($hWndMain, $GWL_STYLE)


$msg = GUIGetMsg(1)
Switch $msg[0]

When I run this, I get a run time error:

"Variable used without being declared"

Edited by StringingLong

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You just need to include Constants.au3

When the words fail... music speaks

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Thanks Andreik. Yes, I just figured this out after looking at the source UDF. This puzzled me because after compiling and building, it did not catch the missing symbol.

It wasn't until after program execution that this error came up. Shouldn't constants be resolved at compile time?

This was a devil of a bug to track down because it was a run time program crash with no error messages.

Edited by StringingLong

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If you compile from within SciTE4AutoIt3, the Au3Check run will catch it. If you run Aut2Exe directly it will compile normally as $GWL_STYLE is "just another variable". :)

It really is worth downloading and using the enhanced version rather than the "SciTE-lite" which you get with the standard Autoit install. ;)


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