Re: Ties within chords inconsistency

[Simon Albrecht]

Am 09.09.2015 um 08:28 schrieb David Kastrup:
> Simon Albrecht <address@hidden> writes:
>
> > Am 04.09.2015 um 04:09 schrieb David Kastrup:
> > > Simon Albrecht <address@hidden> writes:
> > >
> > > > Hello,
> > > >
> > > > consider the following example:
> > > > %%%%%%%%%%%%
> > > > \version "2.19.25"
> > > >
> > > > \new Voice << { c''^~ c'' } { a'_~ a' } >>
> > > >
> > > > \new Voice << { <c''^~> c'' } { <a'_~> a' } >>
> > > >
> > > > { <c''^~ a'_~> <c'' a'> }
> > > > %%%%%%%%%%%%
> > > >
> > > > Contrary to (at least my) expectation the first example gives
> > > >
> > > > tie-within-chord.ly:6:33 <0>: warning: Two simultaneous tie events,
> > > > junking this one
> > > >
> > > > \new Voice << { c''^~ c'' } { a'
> > > >
> > > > _~ a' } >>
> > > >
> > > > and applies the first tie to both notes.
> > > > The other two give correct output, and it would serve consistency and
> > > > predictability if the first did also.
> > > >
> > > > Possibly related: <http://sourceforge.net/p/testlilyissues/issues/2240/>.
> > > No, even before the infamous issue 2240 ("Don't wrap EventChord around
> > > rhythmic events by default.") an in-chord tie on an individual note and
> > > an independent tie event would have behaved in that manner.  Before
> > > issue 2240, the input would have been translated into what is now
> > >
> > > \new Voice << { <c''>^~ <c''> } { <a'>_~ <a'> } >>
> > >
> > > \new Voice << { <c''^~> <c''> } { <a'_~> <a'> } >>
> > >
> > > { <c''^~ a'_~> <c'' a'> }
> > >
> > > and the _result_ from typesetting your input is just like before issue 2240.
> > <https://sourceforge.net/p/testlilyissues/issues/4597/>
> >
> > My ‘possibly related’ statement was only supposed to indicate that
> > these issues have similar topics and are likely concerned with similar
> > parts of the code.
> Uh, this is _not_ a bug and _not_ an inconsistency.  LilyPond
> differentiates in-chord ties and whole-chord ties (as with most other
> articulations).  Using parallel music does not magically change the
> in-chord or out-of-chord character of articulations.  Multiple
> whole-chord ties are redundant and flagged.

Ok, this is convincing as an internal explanation for the current 
behaviour. However, from the user’s point of view the two notations are 
equivalent and it is not desirable to have them behave differently. IMO 
it would be a step forward if the user would not need to know this 
internal distinction and recall when to write <c~> or c~. The current 
situation impedes workflow: without direction indicators, I don’t need 
<> either; if later a direction indicator is required, I have to add <> 
also.
Of course this means reconsidering the relation and the handling of 
in-chord and whole-chord ties, but that shouldn’t keep us from looking 
for a fix, should it? It’s not important whether we call it a defect or 
an enhancement, then.

I think we need more opinions on this. Anyone?

Yours,
Simon