Re: pragma/aspect Import, Convention parameters

[gautier_niouzes@hotmail.com]

Le vendredi 14 août 2015 01:42:30 UTC+2, David Botton a écrit :
> In GWindows I used expressions based on the Win32 API that one chose to support. Windows has a duplicate Ansi and UNICODE set of APIs. It worked out well.

It work*s*, and to the full satisfaction of its users :-) !
To be more concrete, GWindows spec. has this (the file gwindows.ads depends on whether ANSI or UNICODE is used):

   Character_Mode_Identifier : constant String := "W";

and there are at hundreds of places in children packages:

   procedure GetTextMetrics
     (HDC : in  GWindows.Types.Handle;
      M   : out Font_Metrics_W);
   pragma Import (StdCall, GetTextMetrics,
                    "GetTextMetrics" & Character_Mode_Identifier);

So, having the convention as a string could be helpful if one needs to switch between C and StdCall as well.
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