
What is the purpose of the #define directive in C++?
Nov 27, 2015 · In the normal C or C++ build process the first thing that happens is that the PreProcessor runs, the preprocessor looks though the source files for preprocessor directives …
Is it possible to use a if statement inside #define?
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 …
c++ - What does ## in a #define mean? - Stack Overflow
In other words, when the compiler starts building your code, no #define statements or anything like that is left. A good way to understand what the preprocessor does to your code is to get …
c++ - 'static const' vs. '#define' - Stack Overflow
Oct 28, 2009 · #define is a compiler pre processor directive and should be used as such, for conditional compilation etc.. E.g. where low level code needs to define some possible …
c - #Define VS Variable - Stack Overflow
Jun 18, 2012 · The scope of #define is limited to the file in which it is defined. So, #defines which are created in one source file are NOT available in a different source file. In short, #defines …
c++ - Why use #define instead of a variable - Stack Overflow
May 14, 2011 · Most compilers will allow you to define a macro from the command line (e.g. g++ -DDEBUG something.cpp), but you can also just put a define in your code like so: #define …
c# - Define #define, including some examples - Stack Overflow
#define is a special "before compile" directive in C# (it derives from the old C preprocessor directives) that defines a preprocessor symbol. Coupled with #if , depending on what symbols …
c# - How do you use #define? - Stack Overflow
Aug 19, 2008 · #define is used to define compile-time constants that you can use with #if to include or exclude bits of code. #define USEFOREACH #if USEFOREACH foreach(var item in …
Explicitly Define Datatype in Python Function - Stack Overflow
You could indeed perform those check, at the cost of increased volume and complexity of code. The pythonic way is to assume the happy path (all types correct) is being followed, and cross …
What's the difference in practice between inline and #define?
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 …