© Mikael Olsson 2020
M. OlssonC++20 Quick Syntax Referencehttps://doi.org/10.1007/978-1-4842-5995-5_24

24. Preprocessor

Mikael Olsson1 
Hammarland, Finland
The preprocessor is a text substitution tool that modifies the source code before the compilation takes place. This modification is done according to the preprocessor directives that are included in the source files. The directives are easily distinguished from other programming code in that they start with a hash sign (#). They must always appear as the first non-whitespace character on a line, and they do not end with a semicolon. The following table shows the preprocessor directives available in C++ along with their functions.




File include


Macro definition ...

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