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The Preprocessor

Text substitution before the compiler ever runs: object and function macros, header guards, conditional compilation, and why a naive MAX macro evaluates its argument twice.

25 min read

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5 interview questions on this topic

Each one opens a full worked answer.

What's wrong with #define SQUARE(x) x * x?What is double evaluation in a macro, and why does it matter?What is an include guard and what problem does it solve?When should you use a macro versus a const or inline function?How does conditional compilation help in embedded projects?

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The Preprocessor | EmbeddedPrep.io