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Complex Macros

Started by Thunder_Hawk Mar 16, 2003 at 5:40 PM 7 replies 400+ views

Original Post

Mar 16, 2003 at 5:40 PM

  
#define MAKENEW(x) #define x SOMETHING_ELSE

Is there any way to accomplish what I''m trying to do here? ______________________________ And the Phoenix shall rise from the ashes... --Thunder_Hawk -- ¦þ ______________________________

Fruny

203

Fruny

Mar 16, 2003 at 5:44 PM

No.

Sneftel

297

Sneftel

Mar 16, 2003 at 5:44 PM

Nope.

How appropriate. You fight like a cow.

Thunder_Hawk

Author

Thunder_Hawk

Mar 16, 2003 at 5:45 PM

You mean there isn''t any way to escape a # sign in a macro?

Fruny

203

Fruny

Mar 16, 2003 at 5:48 PM

Macros cannot contain other preprocessor directives ( beside the ''stringizing'' # and the ''token pasting'' ## ).

Thunder_Hawk

Author

Thunder_Hawk

Mar 16, 2003 at 6:02 PM

Interesting...back to the drawing board I guess

BTW, this is nothing important I''m just kind of tossing around ideas on things I might do, and this seemed like something neat to try out.

NickB

Mar 16, 2003 at 9:16 PM

on presumption that you wanted to transform x before it got to the first #define, why not just transform it in the define ?

hewhay

Mar 16, 2003 at 11:11 PM

I think that you are trying to declare variables using names dependant on runtime data (??). If it so, i guess that a dictionary implementation (maybe a hash table if you are interested on performance and not memory) would be a better solution. Also defines work at compile time so if your syntax weren''t incorrect it would have been the same to use #define y SOMETHING_ELSE and MAKENEW (y)

Fruny

203

Fruny

Mar 17, 2003 at 5:34 AM

quote:
Original post by hewhay
Also defines work at compile time so if your syntax weren''t incorrect it would have been the same to use #define y SOMETHING_ELSE and MAKENEW (y)

Actually, #define operate before compile-time. That''s why they are called preprocessor macros, and why they let you do things without any language checking. That''s also why preprocessor macros do not respect scope, types ...

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