Weird comment bugs

eyapp2pegex.pgx

# "Atoms"
E_CODE : /(
   <C_LCURLY>
   (:
      [^ <C_LCURLY><C_RCURLY> ]+ |  # Most stuff
      (?1)                          # Nesting braces
   )*
   <C_RCURLY>
)/
E_PERCODE  : / <PERCENT><E_CODE> ~ /  # bit of a hack, as it swallows the % from %}\n
E_BEGINCODE: / <PERCENT> begin ~ <E_CODE> ~ /
E_IDENT    : / (: <ALPHA> | <UNDER> ) <WORD>* ~ /
E_LABEL    : / <COLON> <WORD>+ ~ /
E_LITERAL  : / <SINGLE> [^ <SINGLE> ]+ <SINGLE> ~ /
E_NAME     : / <PERCENT> name ~ /
E_nameident: / ( <E_NAME> ~ (<E_IDENT>) ~ )? /
E_OPTION   : / <E_nameident> <QMARK> ~ /
E_PLUS     : / <E_nameident> <PLUS> ~ /
E_PREC     : / <PERCENT> prec ~ /
E_PLUS     : / <E_nameident> <STAR> ~ /

# Main rule
eyapp:   head body tail

# Common rules:
symbol:  E_LITERAL | ident
ident:   E_IDENT

# Head section:
head:    decl* / ~ <PERCENT><PERCENT> ~ /
decl:    / [ ^<DOS> ]* <EOL> / | E_PERCODE ~

# Rule section
body:    rules* / ~ <PERCENT><PERCENT> ~ /
rules:   / (<E_IDENT>) ~ <COLON> ~ / rhss ~ <SEMI> ~
rhss:    ( <rule>2+ % / ~ <PIPE> ~ / ) | rule
rule:    optname? rhselt* ( prec code? )?

rhselt:
     symbol
   | code
   | E_PREC ident
   | <LPAREN> optname? rhseltwithid* <RPAREN>
   # (not used in Pg.eyp)
   | rhselt (
        E_STAR
      | E_OPTION
      | E_PLUS
      | <LANGLE> ( E_STAR | E_PLUS ) symbol <LANGLE>
   )
;

optname: E_NAME ( E_IDENT E_LABEL? | E_LABEL )  # (not used in Pg.eyp)
prec:    E_PREC ~ symbol
code:    E_CODE | E_BEGINCODE

# Tail section:
tail:    / ( <ALL>+ ) /