May 14, 2011 · What is the point of #define in C++? I've only seen examples where it's used in place of a "magic number" but I don't see the point in just giving that value to a variable instead.

The question is if users can define new macros in a macro, not if they can use macros in macros.

The #define directive is a preprocessor directive; the preprocessor replaces those macros by their body before the compiler even sees it. Think of it as an automatic search and replace of your source code. …

#ifdef DEBUG #define DEBUG_TEST 1 #else #define DEBUG_TEST 0 #endif And then use DEBUG_TEST where I used DEBUG. If you insist on a string literal for the format string (probably a …

Oct 28, 2009 · Is it better to use static const variables than #define preprocessor? Or does it maybe depend on the context? What are advantages/disadvantages for each method?

How can I use #if inside #define in the C preprocessor? Ask Question Asked 15 years, 10 months ago Modified 11 months ago

Jul 12, 2011 · I want to define a two-dimensional array without an initialized length like this: Matrix = [][] But this gives an error: IndexError: list index out of range

As far as I know, what you're trying to do (use if statement and then return a value from a macro) isn't possible in ISO C... but it is somewhat possible with statement expressions (GNU extension). Since …

Jun 18, 2012 · #define WIDTH 10 is a preprocessor directive that allows you to specify a name (WIDTH) and its replacement text (10). The preprocessor parses the source file and each occurrence of the …

Aug 24, 2010 · Macros (created with #define) are always replaced as written, and can have double-evaluation problems. inline on the other hand, is purely advisory - the compiler is free to ignore it. …