#5749 Special-case syntax error of duration before octave marks

[David Kastrup]

Special-case syntax error of duration before octave marks

A somewhat common note-entry error is to write something like c4''
that is (judging from my own experience) not even unusual for
experienced users to fall victim to occasionally. So make a special
parser rule that deals "correctly" with that entry and delivers a more
helpful error message than the parser would muster on its own.

http://codereview.appspot.com/557410043

[David Kastrup]

Example error message:

/usr/local/tmp/lilypond2/out/bin/lilypond ba.ly
GNU LilyPond 2.21.0
Processing `ba.ly'
Parsing...
ba.ly:3:5: error: octave marks must precede duration
{ a1
    ,, }
Interpreting music...
Preprocessing graphical objects...
Finding the ideal number of pages...
Fitting music on 1 page...
Drawing systems...
Layout output to `/tmp/lilypond-X2JzE8'...
Converting to `ba.pdf'...
Deleting `/tmp/lilypond-X2JzE8'...
fatal error: failed files: "ba.ly"

Compilation exited abnormally with code 1 at Tue Feb 11 17:41:27

Without the patch:

Compilation started at Tue Feb 11 17:44:29

lilypond /tmp/ba.ly
GNU LilyPond 2.21.0
Processing `/tmp/ba.ly'
Parsing...
/tmp/ba.ly:3:5: error: syntax error, unexpected ','
{ a1
    ,, }
/tmp/ba.ly:3:1: error: errors found, ignoring music expression

{ a1,, }
fatal error: failed files: "/tmp/ba.ly"

Compilation exited abnormally with code 1 at Tue Feb 11 17:44:30

[Anonymous]

Passes make, make check and a full make doc.

[Anonymous]

Patch on countdown for Feb 16th.

[Anonymous]

Patch counted down - please push.

[Anonymous]

Issue 5749: Special-case syntax error of duration before octave marks master staging
author  David Kastrup <dak@gnu.org> 
    Tue, 11 Feb 2020 16:06:49 +0000 (17:06 +0100)
committer   David Kastrup <dak@gnu.org> 
    Sun, 16 Feb 2020 13:26:50 +0000 (14:26 +0100)
commit  ce072002412d48f48cc4ff4620d82f700e816225