Re: [Lilypond-auto] Issue 2584 in lilypond: please make partcombine merge slurs

[lilypond]

Comment #11 on issue 2584 by address@hidden: please make partcombine merge  
slurs
http://code.google.com/p/lilypond/issues/detail?id=2584

The partcombiner does not actually touch the spanner-id as far as I can  
tell: every slur has the default "" as spanner-id.  If the  
slur-engraver "should know from the spanner-ids that these events refer to  
a single slur" then the consequence is simply that we effectively keep only  
one starting slur event for an identical spanner-id.  But that means that  
we can't support multiple ending events with the same id at different  
points of time, because the first ending event will already cancel the  
remaining starting event.

Instead of relaxing the warning circumstances to a level where a lot of  
clearly wrong manual input gets let through and interpreted in interesting  
ways, it would make more sense to fix the output from the part combiner.   
This should, for one thing, produce matched parens.  For another, it might  
be necessary to actually generate spanner-id's resolving ambiguities.