Info Catalog
m4: Definitions
m4: Top
m4: Debugging
6 Conditionals, loops, and recursion ************************************ Macros, expanding to plain text, perhaps with arguments, are not quite enough. We would like to have macros expand to different things, based on decisions taken at run-time. For that, we need some kind of conditionals. Also, we would like to have some kind of loop construct, so we could do something a number of times, or while some condition is true.
· Ifdef Testing if a macro is defined · Ifelse If-else construct, or multibranch · Shift Recursion in 'm4' · Forloop Iteration by counting · Foreach Iteration by list contents · Stacks Working with definition stacks · Composition Building macros with macros