[antlr-interest] Lexer Compiles in 4.0 but not in 3.4

[Christian]

BININT,OCTINT,DECINT,HEXINT can never be matched because INT catches them all before. Declare these 4 rules as fragment and your grammar should work.

Regards,
Christian

Am 31.01.2012 00:56, schrieb Hans Uhlig:
> Hi all, I am a bit confused. My Lexer Grammar seems to compile fine in
> antlr 4.0 but seems to have trouble in 3.4 Perhaps I am being daft but I
> cant for the life of me figure out why.
>
> error(208): essex_lexer.g:23:1: The following token definitions can never
> be matched because prior tokens match the same input:
> BININT,OCTINT,DECINT,HEXINT
>
> http://pastebin.com/FUWQjpvj
>
> lexer grammar essex_lexer;
>
> ID      :   ('a'..'z'|'A'..'Z'|'_') ('a'..'z'|'A'..'Z'|'0'..'9'|'_')* ;
>
> INT     :   BININT
>         |   OCTINT
>         |   DECINT
>         |   HEXINT
>         ;
>
> BININT  :   '0b' BIN_DIGIT+
>         ;
>
> OCTINT  :   '0o' OCT_DIGIT+
>         ;
>
> DECINT  :   DIGIT+
>         ;
>
> HEXINT  :   '0x' HEX_DIGIT+
>         ;
>
> FLOAT   :   DIGIT+ '.' DIGIT+ EXPONENT?
>         |   DIGIT+ EXPONENT
>         |   DIGIT+ 'f'
>         ;
>
> fragment
> BIN_DIGIT
>         :   ('0' | '1')
>         ;
>
> fragment
> OCT_DIGIT
>         :   ('0'..'7')
>         ;
>
> fragment
> DIGIT
>         :   ('0'..'9')
>         ;
>
> fragment
> HEX_DIGIT
>         :   (DIGIT | 'a'..'f' | 'A'..'F')
>         ;
>
>
> fragment
> EXPONENT:   ('e'|'E') ('+'|'-')? DIGIT+ ;
>
> WS      :   ( ' ' | '\t' | '\r' | '\n' ) {$channel=HIDDEN;} ;
>
> STRING  :   '"' ( ESC_SEQ | ~('\\'|'"') )* '"' ;
>
> CHAR    :   '\''( ESC_SEQ | ~('\''|'\\')) '\'' ;
>
> fragment
> ESC_SEQ :   '\\' ('\\'|'\''|'\"'|'a'|'b'|'f'|'n'|'r'|'t'|'v') | OCT_ESC |
> HEX_ESC | UNICODE_ESC ;
>
> fragment
> HEX_ESC :   '\\x' HEX_DIGIT HEX_DIGIT ;
>
> fragment
> OCT_ESC
>         :   '\\' ('0'..'3') ('0'..'7') ('0'..'7')
>         |   '\\' ('0'..'7') ('0'..'7')
>         |   '\\' ('0'..'7')
>         ;
>
> fragment
> UNICODE_ESC
>         :   '\\u' HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
>         |   '\\U' HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
> HEX_DIGIT HEX_DIGIT HEX_DIGIT
>         ;
>
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