Greetings,
a while back I asked lilypond-user how to engrave a tie between
enharmonic variants, such as g sharp in one bar and a flat in the next
after a key change. The reponse was that not only does lilypond not do
this, but you cannot even typeset the tie manually by \overriding
something. I was also told that there had been a discussion about the
question previously, but I cannot find it in the archives - therefore
allow me to make my proposition here.
I feel that lilypond should not silently refuse to tie enharmonic
variants if the user explicitly requests it. Choral music is
frequently notated like this, to help singers through key changes that
involve shifting from sharp to flat or vice versa. In keyboard music,
there is no difference between enharmonic variants at all, since there
is only one key for both. I therefore propose the following patch: