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GNU macro processor

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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.


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