On Monday, 7 October '02, Hans Breuer wrote: > At 18:50 07.10.02 +0200, Steffen Macke wrote: >>Trying to compile, I get a lot >>of "redefinition of ..." errors. > > Sorry for the incovenience. The M$ compiler docs claim this construct to > be correct (there is no warning at all for the redefinition and at least > for C++ this is standard conform :) See : > http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclang98/ht > ml/_pluslang_redeclaration_of_typedef_names.asp
For ANSI C, declarator identifiers have to be unique (see K&R 2.ed p216 and 219). So it's a no-no. >>Should the lines like >> >>typedef struct _DiaRenderer DiaRenderer; >> >>be replaced by matching #include statements? >> > this would give the 'circular header dependencies', e.g. object.h > needs to include diarenderer.h and vice versa, which I tried to > avoid. IMO the best solution would be a dia-types.h file only > to define the common typedef's something like > > #ifndef DIA_TYPES_H > #define DIA_TYPES_H > typedef struct _Layer Layer; > typedef struct _DiagramData DiagramData; > typedef struct _DiaRenderer DiaRenderer; > #endif > > This would allow to pass partly known 'class' pointers without > exposing any details of the concrete class definitions. > > What do others think about this ? There are several instances of circular includes because of structures needing to know the size of types. Having a separate dia-types.h (or just types.h) should get us rid of most, if not all, circularities. -Lars -- Lars Clausen (http://shasta.cs.uiuc.edu/~lrclause)| Hårdgrim of Numenor "I do not agree with a word that you say, but I |---------------------------- will defend to the death your right to say it." | Where are we going, and --Evelyn Beatrice Hall paraphrasing Voltaire | what's with the handbasket? _______________________________________________ Dia-list mailing list [EMAIL PROTECTED] http://mail.gnome.org/mailman/listinfo/dia-list FAQ at http://www.lysator.liu.se/~alla/dia/faq.html Main page at http://www.lysator.liu.se/~alla/dia
