Hi,
I'm hoping that someone can point me into the right direction here. I'm
trying to gain a bit of a better understanding on how the preprocessor
works - something that seems like a simple topic! I just keep running into
problems (Windows platform) because files are included in the wrong order,
one include file messes up the other one etc.. I think I need to brush up on
some basics here.
In this example project, I have several cpp files (~10) that all pretty much
include one common header file. In Visual Studio I turned the option on to
actually generate those pre-processed files - so that I could see what's
actually going on behind the scenes.
Well, I expected one big file but instead got one preprocessor file for each
of the cpp files in the project. OK, I suppose that this makes sense. One of
the things however I'm constantly trying to do is to prevent header files
from being included more than once - do I not need to worry about this when
it's included from different cpp files?
Also, when I #define macros and put them at the beginning of the header file
like
#ifndef HEADERFILE1_H
#define HEADERFILE1_H
....
...
#endif
then those macro definitions don't seem to stick. When the next cpp files is
being processed, the header file is being included again - even though the
macro was previously defined
Is this normal, and where am I getting confused?
Thanks!
Flo.
Jul 22 '05
12  1584 
"Florian" <wi*******@gmxR EMOVEUPPERCASE. net> wrote in message
news:3l******** *******@newssvr 28.news.prodigy .com... Thanks Ali,
That makes more sense now. I didn't know that in CPP each file was it's
own translation unit. I suppose that's not the case in C then, correct?
Not correct. C and C++ have the same compilation model.
john
Florian wrote: Thanks Ali,
That makes more sense now. I didn't know that in CPP each file was it's own
translation unit. I suppose that's not the case in C then, correct?
C source files are complied the same as C++. Each is its own translation
unit.
Florian wrote:
Thanks Ali,
That makes more sense now. I didn't know that in CPP each file was it's own
translation unit. I suppose that's not the case in C then, correct?
Same thing
--
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