Re: GOP2-3 - GLISS or not

[Joseph Rushton Wakeling]

On 26/07/12 16:50, David Kastrup wrote:
> Joseph Rushton Wakeling <address@hidden> writes:
> > How feasible is it for LilyPond to support a deprecation mechanism for
> > syntax?
>
> At some time, it will be removed or the warning is pointless.  So this
> will not address the topic of bitrot for large mostly dormant bodies of
> music like Mutopia satisfactorily.

Indeed.  But a well-defined deprecation cycle which gives an organization like 
Mutopia time to update its contents may be preferable to freezing LP syntax.

After all, there's value in the contents of an archive like Mutopia being 
maintained over time.  Engraved music needs fixing for many reasons -- errors, 
previously-unidentified performance issues, responses to new scholarship -- you 
don't want them to be just dumped there and left untouched.

The PDFs are still there for the truly unmaintained documents, so it's not like 
you're fundamentally losing the archived music.

> > My overall feeling on this is that while there are areas of "standard"
> > modern musical notation
> > [e.g. https://code.google.com/p/lilypond/issues/detail?id=1278 ] that
> > aren't supported by LilyPond, it's difficult to guarantee syntax
> > stability.  So perhaps a first step is to define the subset of
> > _musical_ notation that you want to provide stable support for.
>
> Sounds to me like that was what Graham proposed in the first place.

No, Graham proposed freezing a subset of _Lilypond syntax_.  I'm proposing that 
before doing any such thing it's important to look at Lilypond's musical 
coverage and ask if it is adequate enough to guarantee that the syntax can be 
stabilized.

The microtonal notation issue I highlighted is relevant in this respect because 
it's almost guaranteed to involve a rewrite of how LP considers pitches and 
pitch alterations internally.  In turn, that might impact all the way back up to 
a rewrite of LP syntax for those things.  And it's a completely standard part of 
modern musical notation that is currently unsupported by Lilypond.