a very simple macro but also very helpful - the varname is usually the one from an AC_ARG_ENABLE or AC_ARG_WITH option. it is transliterated into uppercase and a prefix WITH_ and WITHOUT_ that are both _SUBSTed.
Only one of these is set to "#" while the other is empty. In other words a call like AC_WITHNONE(enable-call) will create two SUBST-symbols as WITH_ENABLE_CALL and WITHOUT_ENABLE_CALL. When the varname had been set to something not "no" or "0" or ":" or "false" then it results in
WITH_ENABLE_CALL="" ; WITHOUT_ENABLE_CALL="#"
which you can use in your Makefile quite easily as if using an AM_CONDITIONAL but which can be also parsed by normal make
USE = @WITH_ENABLE_CALL@ -Denabled USE = @WITHOUT_ENABLE_CALL@ -Dnot_enabled
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Copyright © 2008 Guido U. Draheim firstname.lastname@example.org
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