Define Collateral Information

Understanding define collateral information requires examining multiple perspectives and considerations. 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 extension). From another angle, since #define s are essentially just fancy text find-and-replace, you have to be really careful about how they're expanded.

I've found that this works on gcc and clang by default: What is the difference between #define and const? 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. Similarly, a const variable declaration declares an actual variable in the language, which you can use...

well, like a real variable: take its address, pass it around, use it, cast/convert it, etc. How to declare variable and use it in the same Oracle SQL script?. I want to write reusable code and need to declare some variables at the beginning and reuse them in the script, such as: DEFINE stupidvar = 'stupidvarcontent'; SELECT stupiddata FROM stupidtable ... How do I define a function with optional arguments?.

Asked 13 years, 8 months ago Modified 1 year, 4 months ago Viewed 1.2m times c# - How do you use #define? Similarly, 8 #define is used to define compile-time constants that you can use with #if to include or exclude bits of code. Array format for #define (C preprocessor) - Stack Overflow. Probably a naïve question - I used to program 20 years ago and haven't coded much since.

My memory of how the C preprocessor works has atrophied significantly since then... I am writing a very sim... Furthermore, how do I declare a global variable in VBA? You'll need to complete a few actions and gain 15 reputation points before being able to upvote. Upvoting indicates when questions and answers are useful.

What's reputation and how do I get it? In relation to this, instead, you can save this post to reference later. In relation to this, what is the purpose of the #define directive in C++?. 0 in C or C++ #define allows you to create preprocessor Macros.

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 like #define or #include and then performs simple operations with them. error Please #define _AFXDLL or do not use /MD [d] occurs even after .... Check what Michael said: in the build log, is there a _AFXDLL?