extensions2_tutorial.ac

MOO_XT_DECLARE_EXTENSIONS([
#| Everything above this line is boilerplate; do not edit.

#| Run "autoconf -f" after any changes to extensions2.ac

#| To start the tutorial (see Extensions.md), copy this file to
#| extensions2.ac, make that writable and do all editing there.

#| And yes, this file is nothing but comments and,
#| in its initial state, does nothing.

#| Lines beginning with #| are supposed to stay commented forever.

#| Lines beginning with #(tab) get uncommented at various times;
#| just delete the # but leave the tab there, then put the line
#| back the way it was when it comes time to recomment it.

#| The "TOP" section for tutorial purposes is
#| everything from here down to "[ end of extension declarations ]"

#| This all being the first argument to MOO_XT_DECLARE_EXTENSIONS(),
#| (other arguments except the 9th are M4-expanded and ignored),
#| will be a sequence of cmds in the "MOO_XT Language".

#| Indentation matters in this language.

#	%%extension hello
#	    %disabled
#	    %? Hello Facilities:

#| Only one of these 3 lines should be uncommented:
#	    --enable- hello
#	    --enable- hi
#	    --enable- hi = KWD,...

#	        %?- no hello() function, sorry
#	        %?  provide a hello() function
#	    XT_CSRCS = hello.c
#	    %cdefine HELLO_CORE
#	    %option esmtp HELLO_ESMTP
#	        %alt ehlo
#	        %?   do the esmtp thing

#| Next line is boilerplate; do not edit.
],,,,,,,,[ end of extension declarations ],,,,,,,,

#| Everything from here to the last closing paren is straight
#| autoconf/M4 code that is expanded/evaluated for side-effects only.

#| The main m4 parsing weirdness to know about is that, in argument
#| lists, whitespace after the initial open paren and after any top-level
#| commas gets discarded, but a comment will end whatever run of
#| whitespace it's in, meaning any whitespace *after* the comment
#| (starting on the next line) will be kept and become part of the
#| argument, which may mess things up, so try not to do that.

#| At this point we begin the "MIDDLE" section, for declaring
#| options associated with your extension:

MOO_DECLARE_OPTIONS(

dnl	[[HELLO_ESMTP], [bool], no,  [make hello() do The ESMTP Thing]],
dnl|
dnl| As a general rule, do not use '#' comments in m4 argument lists
dnl| unless you are sure the macro you are invoking can discard them.
dnl|
dnl| MOO_XT_DECLARE_EXTENSIONS, which encloses this whole file,
dnl|   is good at discarding '#' comments;
dnl| MOO_DECLARE_OPTIONS and most other m4 macros are *not*.
dnl|
dnl| So here we use 'dnl' (Delete to NewLine, and that means the
dnl| newline goes away, too) comments which don't have this problem,
dnl| since they expand to *nothing* rather than expanding to themselves
dnl| the way '#' comments do.
dnl|
dnl| You do, however, still want to make sure you do not *INDENT*
dnl| the next line after this comment ends, because that *will*
dnl| introduce whitespace that will not go away.
)

#| ____________________________________________________
#| And, finally, the "BOTTOM" section.  Everything from here to the next
#| line of underscores is for your own macro definitions (m4_define() or
#| AC_DEFUN()) if you need to have any.



#| ____________________________________________________
#| The next closing paren is boilerplate; do not edit.
)dnl| --- end of extensions2.ac ---
dnl|
dnl| We're using 'dnl's here because, now that we're done with
dnl| MOO_XT_DECLARE_EXTENSIONS, we're essentially back out in configure.ac,
dnl| where everything being expanded shows up in ./configure,
dnl| including the '#' comments, which, in this case, is
dnl| not what anyone wants.
dnl|
dnl| Uncomment the next line and rerun autoconf
dnl| if you want to see what the MOO_XT_* things actually do:
dnl MOO_XT_DUMP_EVERYTHING()