What does preprocessing exactly mean in compiler A preprocessor is an "engine" executed before the compiler compiles code #define #include are preprocessor directives or macros, so the preprocessor engine executes code related to the directives
Why should one bother with preprocessor directives? C preprocessor directives macros are just another form of "meta-programming", albeit a relatively cruder form than is available in other languages Preprocessor directives instruct the compiler to do certain things at compile time, such as to ignore certain code on certain platforms, or to find and replace a string in the code with another string
How can I use else if with the preprocessor #ifdef? In my project, the program can do one thing of two, but never both, so I decided that the best I can do for one class is to define it depending of a #define preprocessor variable The following cod
Scope of #define preprocessor in C - Stack Overflow The preprocessor doesn't have any concept of "scope"—it manipulates the text of the program, without any idea of what the text is A symbol is defined from its definition until the end of the compilation unit (a source file and the files it includes)
c - Difference between macro and preprocessor - Stack Overflow Preprocessor directives are like commands to the preprocessor program Some common preprocessor directives in C are #include <header name> - Instructs the preprocessor to paste the text of the given file to the current file
How to compare strings in C conditional preprocessor-directives 0 I've wanted to use string comparison as well in preprocessor macros, mostly so I can also "print" these values during preprocessing step (using pragma message) As mentioned in accepted answer: I don't think there is a way to do variable length string comparisons completely in preprocessor directives
C# Preprocessor - Stack Overflow Interesting I don't really consider a preprocessor to necessarily work this way In the example provided, I am doing a simple text substitution, which is in-line with the definition of a preprocessor on If this isn't the proper use of a preprocessor, what should we call a simple text replacement, which generally needs to occur before a
C preprocessor #if expression - Stack Overflow The preprocessor cannot use variables from the C program in expressions - it can only act on preprocessor macros So when you try to use c in the preprocessor you don't get what you might expect