Re: Error: LilyPond could not Typeset this score

[Richard Shann]

On Wed, 2022-06-15 at 22:56 +0200, Michael Wossog wrote:
> Hi, I have Denemo installed in OpenSUSE and I have used the packages
> created by Edgar.
> When I run Denemo, the Denemo Print View shows the error:

It's not too clear: is this before you have started to create a score?
Or did this come after working with Denemo on a score...

For the former, the problem will be that LilyPond is not installed, or
that it is not in the path, or that the preferences have been changed
to expect it to be somewhere where it is no longer present.

For the latter, I've long been thinking I should write a guide as to
what to do in that situation. I'll write the barest outline here, and
then gradually add to it.

If while working on a score the Print View suddenly stops updating
click on Typeset in the Print View to see an error message. The cursor
may then move to a place in the score where something bad has been
inserted, so look at that place and re-enter anything at that location.
In any event it may be that  by pressing Ctrl-z you can undo the
problem. If not the next thing to try is Check Score.
This however is not comprehensive and if it reports that it can find no
problem there are three ways to go:

1) If you have been using Denemo a good while and "have your eye in"
and your score is not too big you can look over what you have entered
for anything unusual
2) If you have some familiarity with LilyPond syntax you can use the
LilyPond View to typeset and examine the error message there and the
place where the red coloring starts.
3) If your score is not confidential you can mail it to the mailing
list - someone will help.
4) You can take a systematic approach to uncovering the problem as
follows.

The first thing to do is make a backup of your score. 

If the score has several movements try deleting each movement in turn
and re-typeset each time. If it starts to typeset, re-instate the last
movement deleted and delete all the others.

Now you have a single-movement score which will not typeset. Proceed as
follows.

Delete all the music in the score (use 

Command: Select All Music In Movement
Creates a selection for all the music in the current movement.
Location: Main Menu ▶ Edit ▶ Select
Internal Name: SelectAll)

followed by Cut to cut out all the music. The try to typeset.
If it still fails it means the problem is with the definitions for the
score/movement/staffs/voices and not in the music itself. Follow Plan A
below.  If it does now typeset restore all the music and follow Plan B.

Plan A

At this point your score is probably not confidential so you could
email it to the mailing list, alternatively you can use the
Score/Movement/Staff/Voice editors to delete properties (directives)
that you have set until you find the culprit. When you *have* found the
culprit try re-instating the property that you had set to see if you
have found a bug - if so please report it.

Plan B

The problem is with the music entered. The strategy is to make a copy
of the score and then delete half the music - go to the middle and
choose 

Command: Delete Measures From Cursor
Deletes all measures from the cursor to the end, either in one or all
staffs.
Location: Object Menu ▶ Staffs/Voices
Internal Name: DeleteFromCursorToEnd

then see if it typesets. If it does repeat the process until it does
not. If it doesn't restore the deleted music (e.g. via Undo) and halve
the amount you delete. The aim is to isolate the bar which is causing
the problem. When you have the smallest amount that causes the problem
you can inspect for anything unusual and/or re-make the bar that caused
the problem. If possible please copy and paste the troublesome bar into
a blank score and send it to the mailing list - you may have uncovered
a bug.

If anyone can offer further text to this description please do - I'll
add it to the manual in due course.

HTH

Richard