How deeply does Modern C, Third Edition cover macro invocation?

Defines invocation parsing and follows recursive argument expansion, substitution, rescanning, and macro re-enabling.

Macro invocation

A macro invocation is source text consisting of a function-like macro name followed by parentheses containing its arguments.

A macro invocation is a function-like macro name followed by parentheses containing arguments, such as BYTECOPY(A, B). The preprocessor parses balanced parentheses, uses top-level commas to separate arguments, and checks that their number matches the macro parameters. section 17.1

Expansion proceeds in a defined sequence:

Disable the macro temporarily to prevent infinite recursive expansion. section 17.1
Recursively expand macros appearing inside each argument. section 17.1
Substitute the resulting argument text into a copy of the replacement text, then rescan that text for further macro replacement. section 17.1

Expanding BYTECOPY

With #define BYTECOPY(T, S) memcpy(&(T), &(S), MINSIZE(T, S)), an invocation such as BYTECOPY(A, B) expands its arguments, substitutes them into the replacement text, and expands nested MINSIZE calls. A macro invocation can also generate declarations or statement-like code, as in declareColor(color8); or a do ... while(false) wrapper. section 17.1 section 18.1.3

#define BYTECOPY(T, S) memcpy(&(T), &(S), MINSIZE(T, S))

Inspect the BYTECOPY definition to connect invocation syntax with parameter substitution and generated library-call text. section 17.1

How Modern C, Third Edition covers it

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Related concepts

function-like macrouses · A function-like macro is a macro invoked with function-like syntax that accepts token input and expands or transforms it into generated source.
macro expansionproduces · Macro expansion is the compile-time transformation of a macro invocation into source tokens or language constructs according to its definition and expansion rules.
callequivalent to · A function call is an operation or expression that invokes a function or other callable, optionally supplies arguments, and initiates its execution.
quoteuses · quote is a Rust crate and macro for constructing Rust token streams from quasi-quoted syntax.
macrouses · A macro is a named construct that expands or transforms source code, commands, or templates before or during execution.

This explainer was generated by Manning's knowledge graph from the text of Modern C, Third Edition. The section links point to the parts of the book it draws on.