preprocessor token

[unifire]

Hi

I use a define like this to search an element in a linked list

#define SEARCH_NEXT( _Block, _Queue)
{
[...]
_Block = _Block->##_Queue.pNext;
[...]
}

now, I get the following error:

pasting "->" and "Queue" does not give a valid preprocessing token

does anyone know some god literature about this issue

thx

[Walter Roberson]

In article <11**********************@g44g2000cwa.googlegroups .com>,
unifire <un*****@gmx.net> wrote:

I use a define like this to search an element in a linked list
#define SEARCH_NEXT( _Block, _Queue)
{
[...]
_Block = _Block->##_Queue.pNext;
[...]
} now, I get the following error: pasting "->" and "Queue" does not give a valid preprocessing token does anyone know some god literature about this issue

Is there a particular reason you are not just using

#define SEARCH_NEXT( _Block, _Queue) \
{ \
[...] \
_Block = _Block->_Queue.pNext; \
[...] \
}

--
If you lie to the compiler, it will get its revenge. -- Henry Spencer

[Laurent Deniau]

unifire wrote:

Hi

I use a define like this to search an element in a linked list

#define SEARCH_NEXT( _Block, _Queue)
{
[...]
_Block = _Block->##_Queue.pNext;
[...]
}

now, I get the following error:

pasting "->" and "Queue" does not give a valid preprocessing token
remove the ## not required here.
does anyone know some god literature about this issue

look at the definition of the ## operator and/or a token?

a+, ld.

[Kenneth Brody]

unifire wrote:

Hi

I use a define like this to search an element in a linked list

#define SEARCH_NEXT( _Block, _Queue)
{
[...]
_Block = _Block->##_Queue.pNext;
[...]
}

now, I get the following error:

pasting "->" and "Queue" does not give a valid preprocessing token
That's because "->_Queue" is not a valid token. Remove the "##" as
it is unnecessary.
does anyone know some god literature about this issue

I hear that the Bible is pretty good, but I don't think it mentions
the C preprocessor anywhere. :-)

Hold on... Joshua 2:12 says

Now therefore, I pray you, swear unto me by the LORD, since I have
showed you kindness, that ye will also show kindness unto my father's
house, and give me a true token:

--
+-------------------------+--------------------+-----------------------------+
| Kenneth J. Brody | www.hvcomputer.com | |
| kenbrody/at\spamcop.net | www.fptech.com | #include <std_disclaimer.h> |
+-------------------------+--------------------+-----------------------------+
Don't e-mail me at: <mailto:Th*************@gmail.com>

[Peter Nilsson]

Walter Roberson wrote:

<snip>
Is there a particular reason you are not just using

#define SEARCH_NEXT( _Block, _Queue) \
{ \
[...] \
_Block = _Block->_Queue.pNext; \
[...] \
}

I'd prefer the do { } while(0) trick over plain {}; I'd parenthesise
the first
macro parameter in the substitution text; and I'd also change the macro
parameter names...

All identifiers that begin with an underscore and either an uppercase
letter or another underscore are always reserved for any use.

--
Peter