Re: Why is that?

From: Thomas Matthews (Thomas_MatthewsSpitsOnSpamBots_at_sbcglobal.net)
Date: 08/19/04 

Date: Thu, 19 Aug 2004 14:47:16 GMT

Profetas wrote:

> I know what is causing the problem, but I couldn't
> find out why.
>
> #define newline "\n"
> #define question_mark "\?"
> #define single_quotas "\'"
> #define double_quotas "\""
> #define form_feed "\f"
> #define horizontal_tab "\t"
> #define vertical_tab "\v"
> #define backslash "\\"

One of the main problems of the above macros is
that you are using strings instead of characters.

If I have:
   const char statement[] = "Hello\t\"World?\"";
And I want to search for a "question_mark",
I would naturally want to use:
   char * posn;
   posn = strchr(statement, question_mark);
Which will not work because strchr() requires
a single char as the second parameter. Also,
this one will be hard to find:
   posn = strchr(question_mark, statement);
In the above line, the first parameter has the
correct type, but wrong logic.

Also, please check your spelling. Note that
in English, "quota" and "quote" are two different
words. A quota is a limit. One could have a
single quota. There could also be double quotas,
which means having two limits; which is far from
the symbol (").

At some point, macros lead more to obfuscating
a program than to readablility.
If you want to keep down this path, may I also
suggest these macros:
#define begin {
#define end }
#ifndef and
   #define and &&
#endif
#ifndef or
   #define or ||
#endif
#ifndef not
   #define not !
#endif
#define ever 1
#define forever 1

while (forever)
begin
   if (a and b)
   begin
     continue;
   end
   else
   begin
     break;
   end
end 

-- 
Thomas Matthews
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