Re: Could we do something to promote convert-ly?

[Jean Abou Samra]

Le 08/02/2022 à 21:29, David Kastrup a écrit :
> David Kastrup <dak@gnu.org> writes:
>
> > Jean Abou Samra <jean@abou-samra.fr> writes:
> >
> > > Folks,
> > >
> > > I am getting tired at the number of questions of the type
> > > "Why doesn't this work anymore?" which can be answered by
> > > "Just Run convert-ly! (TM)". I suspect that the effort we
> > > put in crafting convert-ly rules is not paying in perceived
> > > backwards compatibility as users don't think about running
> > > convert-ly, or perhaps don't even know about it. Could we
> > > do something to change this?
> > >
> > > Some ideas:
> > >
> > > - Mention it in release announcements,
> > > - Mention it in the Changes document,
> > > - When the score produces an error and the \version
> > >    statement is for a different minor version number,
> > >    print a warning ("compilation failed and \version
> > >    statement is outdated, did you update syntax with
> > >    convert-ly?" or something like that).
> > >
> > > Thoughts?
> > Different major number.  Possibly also odd major number and different
> > minor number, but I guess stable releases are done frequently enough
> > these days that it's unlikely a distribution will package an unstable
> > one.
> An extra bit of work would be maintaining a list of regexps since the
> last major version that would trigger the message, with the message
> always being triggered for a major version change.  If we want to avoid
> calling a Python interpreter, the regexps should likely be Guile
> regexps.


Well, lexer.ll contains

Lilypond_version oldest_version ("2.7.38");

bool
is_valid_version (string s)
{
  ...
  if (ver < oldest_version)
    {
        non_fatal_error (_f ("file too old: %s (oldest supported: %s)", 
ver.to_string (), oldest_version.to_string ()));
        non_fatal_error (_ ("consider updating the input with the 
convert-ly script"));
        return false;
    }
  ...
}

where oldest_version has not been updated in 15 years.
What you suggest would be nice in theory but I am wary
of maintenance.