Issue 2598: Allow brackets and parens to start lyrics, disallow "accents"

[] and () are considered as punctuation in lyrics and can start them.
In contrast, "TeX accents" \' \" \` \^ are quite ridiculous to
"support" in lyrics since LilyPond has not been using TeX for a long
time now, so those sequences are no longer considered special in
lyrics.

diff --git a/lily/lexer.ll b/lily/lexer.ll
index bdbf1283141e643d28d2216b381cddd5184586a9..a56c182eab1d1d4067d590f898593e63c23e9ddf 100644 (file)
--- a/lily/lexer.ll
+++ b/lily/lexer.ll
@@ -152,11 +152,10 @@ AA                {A}|_
 N              [0-9]
 AN             {AA}|{N}
 ANY_CHAR       (.|\n)
-PUNCT          [?!:'`]
-ACCENT         \\[`'"^]
+PUNCT          [][()?!:'`]
 SPECIAL_CHAR           [&@]
 NATIONAL       [\001-\006\021-\027\031\036]
-TEX            {AA}|-|{PUNCT}|{ACCENT}|{NATIONAL}|{SPECIAL_CHAR}
+TEX            {AA}|-|{PUNCT}|{NATIONAL}|{SPECIAL_CHAR}
 DASHED_WORD            {A}({AN}|-)*
 DASHED_KEY_WORD                \\{DASHED_WORD}