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Konrad
Guest
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 Posted: Sun Feb 26, 2006 6:06 pm Post subject: #defines and multiline expressions |
 |
|
Hello,
Stupid question, but I just don't remember, here is what I want to do:
#ifdef _UNICODE
#define ONLY_UNICODE(t) t
#else
#define ONLY_UNICODE(t)
#endif
You know what it does, but I'm not sure, if I actually can use #defines
with multiline code? I'm just not sure, here is an example of using this:
ONLY_UNICODE
(
MessageBox(_T("A lot of lines"));
MessageBox(_T("are included"));
MessageBox(_T("as a paremeter of this directive"));
);
It does compile, but maybe I should be worry about it ? I do remember
that there was something about including more than one line as a
#define's parameter, I somehow don't remember what was that. |
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David Lindauer
Guest
|
| Posted: Sun Feb 26, 2006 7:06 pm Post subject: Re: #defines and multiline expressions |
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|
Konrad wrote:
| Quote: | Hello,
Stupid question, but I just don't remember, here is what I want to do:
#ifdef _UNICODE
#define ONLY_UNICODE(t) t
#else
#define ONLY_UNICODE(t)
#endif
You know what it does, but I'm not sure, if I actually can use #defines
with multiline code? I'm just not sure, here is an example of using this:
ONLY_UNICODE
(
MessageBox(_T("A lot of lines"));
MessageBox(_T("are included"));
MessageBox(_T("as a paremeter of this directive"));
);
It does compile, but maybe I should be worry about it ? I do remember
that there was something about including more than one line as a
#define's parameter, I somehow don't remember what was that.
|
#define ONLY_UNICODE( \
MessageBox(_T("A lot of lines")); \
MessageBox(_T("are included")); \
MessageBox(_T("as a paremeter of this directive")); \
);
might work... the '\' means concatenate two lines together... |
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Konrad
Guest
|
| Posted: Sun Feb 26, 2006 8:06 pm Post subject: Re: #defines and multiline expressions |
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|
David Lindauer wrote:
| Quote: |
Konrad wrote:
Hello,
Stupid question, but I just don't remember, here is what I want to do:
#ifdef _UNICODE
#define ONLY_UNICODE(t) t
#else
#define ONLY_UNICODE(t)
#endif
You know what it does, but I'm not sure, if I actually can use #defines
with multiline code? I'm just not sure, here is an example of using this:
ONLY_UNICODE
(
MessageBox(_T("A lot of lines"));
MessageBox(_T("are included"));
MessageBox(_T("as a paremeter of this directive"));
);
It does compile, but maybe I should be worry about it ? I do remember
that there was something about including more than one line as a
#define's parameter, I somehow don't remember what was that.
#define ONLY_UNICODE( \
MessageBox(_T("A lot of lines")); \
MessageBox(_T("are included")); \
MessageBox(_T("as a paremeter of this directive")); \
);
might work... the '\' means concatenate two lines together...
|
Thanks, but it's not what I meant, I was not clear enough I 
the "ONLY_UNICODE" is defined OK, it is how it is supposed to be, the
question is: Can I _use_ it as in my example, that is - can I pass
multiline parameter to it, I know it compiles, I just wanted to know if
there are things to be worry about. |
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TB
Guest
|
| Posted: Sun Feb 26, 2006 8:06 pm Post subject: Re: #defines and multiline expressions |
|
|
David Lindauer skrev:
| Quote: |
Konrad wrote:
Hello,
Stupid question, but I just don't remember, here is what I want to do:
#ifdef _UNICODE
#define ONLY_UNICODE(t) t
#else
#define ONLY_UNICODE(t)
#endif
You know what it does, but I'm not sure, if I actually can use #defines
with multiline code? I'm just not sure, here is an example of using this:
ONLY_UNICODE
(
MessageBox(_T("A lot of lines"));
MessageBox(_T("are included"));
MessageBox(_T("as a paremeter of this directive"));
);
It does compile, but maybe I should be worry about it ? I do remember
that there was something about including more than one line as a
#define's parameter, I somehow don't remember what was that.
#define ONLY_UNICODE( \
MessageBox(_T("A lot of lines")); \
MessageBox(_T("are included")); \
MessageBox(_T("as a paremeter of this directive")); \
);
might work... the '\' means concatenate two lines together...
|
I don't think that was what he was asking. He wondered if the macro
argument could span multiple lines. And the answer is yes, with the
exception that possible commas will interfere.
#define MACRO(C) C
int main() {
MACRO
(
int x;
x = 3;
)
return 0;
}
But this doesn't compile:
#define MACRO(C) C
int main() {
MACRO
(
int x,y;
x = 3;
)
return 0;
}
--
TB @ SWEDEN |
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Marc Thrun
Guest
|
| Posted: Sun Feb 26, 2006 9:06 pm Post subject: Re: #defines and multiline expressions |
|
|
TB wrote:
| Quote: | David Lindauer skrev:
snip
#define ONLY_UNICODE( \
MessageBox(_T("A lot of lines")); \
MessageBox(_T("are included")); \
MessageBox(_T("as a paremeter of this directive")); \
);
might work... the '\' means concatenate two lines together...
I don't think that was what he was asking. He wondered if the macro
argument could span multiple lines. And the answer is yes, with the
exception that possible commas will interfere.
#define MACRO(C) C
int main() {
MACRO
(
int x;
x = 3;
)
return 0;
}
But this doesn't compile:
#define MACRO(C) C
int main() {
MACRO
(
int x,y;
x = 3;
)
return 0;
}
|
I would try something like
#ifdef _UNICODE
#define ONLY_UNICODE
#else
#define ONLY_UNICODE while(0)
#endif
int main()
{
ONLY_UNICODE
{
/* code */
}
return 0;
}
This has no problems with commas and a compiler will most likely
optimize the while(0) loop away anyway. |
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Asfand Yar Qazi
Guest
|
| Posted: Sun Feb 26, 2006 11:06 pm Post subject: Re: #defines and multiline expressions |
|
|
Marc Thrun wrote:
| Quote: | TB wrote:
David Lindauer skrev:
snip
#define ONLY_UNICODE( \
MessageBox(_T("A lot of lines")); \
MessageBox(_T("are included")); \
MessageBox(_T("as a paremeter of this directive")); \
);
might work... the '\' means concatenate two lines together...
I don't think that was what he was asking. He wondered if the macro
argument could span multiple lines. And the answer is yes, with the
exception that possible commas will interfere.
#define MACRO(C) C
int main() {
MACRO
(
int x;
x = 3;
)
return 0;
}
But this doesn't compile:
#define MACRO(C) C
int main() {
MACRO
(
int x,y;
x = 3;
)
return 0;
}
I would try something like
#ifdef _UNICODE
#define ONLY_UNICODE
#else
#define ONLY_UNICODE while(0)
#endif
int main()
{
ONLY_UNICODE
{
/* code */
}
return 0;
}
This has no problems with commas and a compiler will most likely
optimize the while(0) loop away anyway.
|
You can have multi-line arguments to argument-taking macros?!?! Bloody hell,
I never knew that!
This could revolutionise something I was stuck on in one of my projects...
--
To reply, take of all ZIGs !!
Alternative email address: emailZIG (AT) asfandyarZIG (DOT) cjbZIG.net |
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Asfand Yar Qazi
Guest
|
| Posted: Sun Feb 26, 2006 11:06 pm Post subject: Re: #defines and multiline expressions |
|
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Asfand Yar Qazi wrote:
| Quote: | Marc Thrun wrote:
TB wrote:
David Lindauer skrev:
snip
#define ONLY_UNICODE( \
MessageBox(_T("A lot of lines")); \
MessageBox(_T("are included")); \
MessageBox(_T("as a paremeter of this directive")); \
);
might work... the '\' means concatenate two lines together...
I don't think that was what he was asking. He wondered if the macro
argument could span multiple lines. And the answer is yes, with the
exception that possible commas will interfere.
#define MACRO(C) C
int main() {
MACRO
(
int x;
x = 3;
)
return 0;
}
But this doesn't compile:
#define MACRO(C) C
int main() {
MACRO
(
int x,y;
x = 3;
)
return 0;
}
|
I must say that I've bettered myself. Try the following code:
#define MACRO(...) __VA_ARGS__
int main() {
MACRO
(
int x,y;
x = 3;
)
}
Note: only works in C99 mode. Worked alright for me on GCC (using g++
front-end as well), don't know about other compilers. But, we're getting
there :-)
--
To reply, take of all ZIGs !!
Alternative email address: emailZIG (AT) asfandyarZIG (DOT) cjbZIG.net |
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Joe Hotchkiss
Guest
|
| Posted: Mon Feb 27, 2006 9:06 am Post subject: Re: #defines and multiline expressions |
|
|
"Konrad" <konradp_removit_ (AT) wp (DOT) pl> wrote in message
news:dtspjf$g69$1 (AT) nemesis (DOT) news.tpi.pl...
| Quote: | Hello,
Stupid question, but I just don't remember, here is what I want to do:
#ifdef _UNICODE
#define ONLY_UNICODE(t) t
#else
#define ONLY_UNICODE(t)
#endif
You know what it does, but I'm not sure, if I actually can use
#defines
with multiline code? I'm just not sure, here is an example of using
this:
ONLY_UNICODE
(
MessageBox(_T("A lot of lines"));
MessageBox(_T("are included"));
MessageBox(_T("as a paremeter of this directive"));
);
|
What's wrong with
#ifdef _UNICODE
MessageBox(_T("A lot of lines"));
MessageBox(_T("are included"));
MessageBox(_T("as a paremeter of this directive"));
#endif
--
Regards,
Joe Hotchkiss,
http://joe.hotchkiss.com
http://harrowsubaqua.org.uk
XXXXXXXXXXXXXXXXXXXXXXXXX
X joe.hotchkiss X
X at selex-sas.com X
XXXXXXXXXXXXXXXXXXXXXXXXX |
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Konrad
Guest
|
| Posted: Mon Feb 27, 2006 7:06 pm Post subject: Re: #defines and multiline expressions |
|
|
(..)
OK, I got it now, thank you all!
| Quote: | What's wrong with
#ifdef _UNICODE
MessageBox(_T("A lot of lines"));
MessageBox(_T("are included"));
MessageBox(_T("as a paremeter of this directive"));
#endif
|
Mine is shorter |
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