Re: user upgrade path for renamed macros

[Peter Simons]

Hi Filippo,

 > Since aclocal prefers files with serial we can set a serial 0 on old
 > files with renamed macros thus aclocal --diff|--install will pick them.
 > Note that these files are bound to be removed anyway from the archive so
 > having them serialized should do no harm beside making the user aware of
 > replacements.

first of all, thank you for taking the time to investigate this approach. My
understanding of the way those serial numbers are handled is very limited,
so please bear with me if I don't get everything right away.

In my perception, the problem we're trying to solve is this one: a macro
AC_FOO_BAR has been renamed to AX_FOO_BAR, and now we'd like users of
AC_FOO_BAR to notice that this change has occurred so that they can update
their configure.ac script. I don't quite see, though, how serial lines would
play into this. I assumed that aclocal would treat those two macros as
distinct (because they have different names)? You said aclocal "prefers"
files with a serial line. What exactly does that mean in our context?


 > In addition to the serial provide also a AU_ALIAS([old_name],[new_name])
 > for autoupdate to pick up (not strictly necessary but read on)

Yes, that makes perfect sense. The obsolete macros should feature an
AU_ALIAS call that points users to the new macro name. From the looks of it,
it shouldn't be too hard to add an appropriate line to all obsolete macros
in the repository. We could probably use sed(1) to serach-and-replace the
corresponding calls to AC_DEFUN.

If you're interested in making that change (or rather, in writing a script
that automates those that changes), I'd be delighted.

Take care,
Peter