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GNU macro processor

4.4 Deleting a macro

A macro definition can be removed with undefine:

undefine(name)

which removes the macro name. The macro name must necessarily be quoted, since it will be expanded otherwise.

The expansion of undefine is void.

foo =>foo define(`foo', `expansion text') => foo =>expansion text undefine(`foo') => foo =>foo

It is not an error for name to have no macro definition. In that case, undefine does nothing.

The macro undefine is recognized only with parameters.