Attempt to define Mercury grammar

mercury_alt.g

grammar mercury_alt;

//options {
// backtrack = true;
// memoize=true;
//}

model:
    s item*;
    
//http://www.mercury.csse.unimelb.edu.au/information/doc-release/mercury_ref/Terms.html#Terms
item: term TERM_END s;

term
	:	 (altFunctor);

listTerm
	:	OPEN_LIST s commaSeparatedFunctors CLOSE_LIST;
	
tupleTerm
	:	OPEN_CURLY s commaSeparatedFunctors CLOSE_CURLY;
	
s	:	 (SL_COMMENT | ML_COMMENT | WS | LINE)*;

commaSeparatedFunctors
	:	 (functor (COMMA s functor)*)?;

altFunctor
	:	 ('?-' s| ':-' s)? altPrec1200;

altPrec1200
	:	altPrec1199 ((':-' s| '-->' s) altPrec1199)?
	;

altPrec1199
	: (('end_module'//                      fx                1199
	|'import_module'//                   fx                1199
	|'include_module'//                  fx                1199
	|'initialise'//                      fx                1199
	|'initialize'//			fx		  1199
	|'finalise'//			fx		  1199
	|'finalize'//			fx		  1199
	|'inst'//                            fx                1199
	|'instance'//                        fx                1199
	|'mode'//                            fx                1199
	|'module'//                          fx                1199
	|'pragma'//                          fx                1199
	|'promise'//                         fx                1199
	|'rule'//                            fx                1199
	|'typeclass'//                       fx                1199
	|'use_module'//                      fx                1199
) s)? altPrec1181;

altPrec1181
	:	('solver' s altPrec1181) | altPrec1180;

altPrec1180
	:	('type' s altPrec1180) | altPrec1179;

altPrec1179
	:	 altPrec1175 ('--->' s altPrec1179)?;
	
altPrec1175
	:	 altPrec1170
	 (('::' |'==>' | 'where') s altPrec1170)?;
	 
altPrec1170
	:	altPrec1160 ('else' altPrec1170)? ;

altPrec1160
	:	 ('if' s)? altPrec1150;

altPrec1150
	:	 altPrec1100 ('then' s altPrec1100)?;
	
altPrec1100
	:	 altPrec1050 (';' s altPrec1100)?;
	
altPrec1050
	:	 altPrec1025 ('->' s altPrec1050)?;

altPrec1025
	:	altPrec1000 ('&' s altPrec1025)?;

altPrec1000
	:	 prec950 (COMMA s altPrec1000)?;


functor
	: ('?-' s| ':-' s)? prec1200;
	
prec1200
	:	prec1199 ((':-' s| '-->' s) prec1199)?
	;

prec1199
	: (('end_module'//                      fx                1199
	|'import_module'//                   fx                1199
	|'include_module'//                  fx                1199
	|'initialise'//                      fx                1199
	|'initialize'//			fx		  1199
	|'finalise'//			fx		  1199
	|'finalize'//			fx		  1199
	|'inst'//                            fx                1199
	|'instance'//                        fx                1199
	|'mode'//                            fx                1199
	|'module'//                          fx                1199
	|'pragma'//                          fx                1199
	|'promise'//                         fx                1199
	|'rule'//                            fx                1199
	|'typeclass'//                       fx                1199
	|'use_module'//                      fx                1199
) s)? prec1181;

prec1181
	:	('solver' s prec1181) | prec1180;

prec1180
	:	('type' s prec1180) | prec1179;

prec1179
	:	 prec1175 ('--->' s prec1179)?;
	
prec1175
	:	 prec1170
	 (('::' |'==>' | 'where') s prec1170)?;
	 
prec1170
	:	prec1160 ('else' prec1170)? ;

prec1160
	:	 ('if' s)? prec1150;

prec1150
	:	 prec1100 ('then' s prec1100)?;
	
prec1100
	:	 prec1050 (';' s prec1100)?;
	
prec1050
	:	 prec1025 ('->' s prec1050)?;

prec1025
	:	prec1000 ('&' s prec1025)?;

prec1000
	:	 prec950 /*(',' s prec1000)?*/;

prec950
	://TODO, how to make it work? It fails because the ambiguite between the prefix + and the infix + in these positions.
//		((('all' | 'arbitrary' | 'promise_equivalent_solutions' | 'promise_equivalent_solution_sets' | 'require_complete_switch' | 'some' ) s) prec920 s prec950) | 
	((('promise_impure' | 'promise_pure' | 'promise_semipure' | 'require_det' | 'require_semidet' | 'require_multi' | 'require_cc_multi' | 'require_cc_nondet' | 'require_erroneous' | 'require_failure') s) prec920) |
	((('promise_exclusive' | 'promise_exclusive_exhaustive' | 'promise_exhaustive') s) prec950) |
	prec920;

prec920
	:	prec900 (('<=' | '<=>' | '=>') s prec920)?;

prec900
	: ((('\\\\+' | 'not' | '~') s) prec900) |
	(prec800 ('when' s prec800)?);

prec800
	: ((('impure' | 'semipure') s) prec800)  |
  prec740 |
	(('func' | 'pred') s prec740);

prec740
 	:	 prec720 ('or' s prec740)?;

prec720
 	:	 prec701 ('and' s prec720)?;

prec701
 	:	 prec700 ('is' s prec700)?;
 	
prec700
	:	 prec650 (('<' | '=' | '=..' | '=:=' | '=<' | '==' | '=\\\\=' | '>' | '>=' | '@<' | '@=<' | '@>' | '@>=' | '\\\\=' | '\\\\==' | '~=') s prec650)?;
	
prec650
	:  prec550 ((':=' | '=^') s prec550)?
	;


prec550
	:	prec500 ('..' s prec500)?;
	
prec500
	: ('+' s prec400 /*why not fy? */) |
//	  (prec400 (('+' s prec400)* | ('++' s prec400)? | ('-' s prec400)* | ('--' s prec400)* | ('/\\\\' s prec400)* | ('\\\\/' s prec400)*));
	  (prec400 (('+' s prec400)+ | ('++' s prec400) | ('-' s prec400)+ | ('--' s prec400)+ | ('/\\\\' s prec400)+ | ('\\\\/' s prec400)+)?);

prec400
//	:	 prec200 (('*' s prec200)* | ('/' s prec200)* | ('//' s prec200)* | ('<<' s prec200)* | ('>>' s prec200)* | ('div' s prec200)* | ('mod' s prec200)? | ('rem' s prec200)?);
	:	 prec200 (('*' s prec200)+ | ('/' s prec200)+ | ('//' s prec200)+ | ('<<' s prec200)+ | ('>>' s prec200)+ | ('div' s prec200)+ | ('mod' s prec200) | ('rem' s prec200))?;
	
prec200
	:	(('-' | '\\\\') s)? prec120 ('**' prec120)?;
	
prec120
	:	prec100 ((':' | ('`' (NAME ((END NAME)*)|VARIABLE) '`')) s prec100)*;
	
prec100
	:	('^' s)? prec99;
	
prec99
	:	prec90 ('^' s prec99)?;
	
prec90
	:	prec40 ('@' s prec40)?;

prec40
	:	(('!' | '!.' | '!:') s)? prec10;

prec10
	:	prec0 ((END ~(WS | SL_COMMENT | ML_COMMENT | EOF))=>'.' prec0)*;

prec0
	:	 (NAME | FLOAT | STRING | parenthezedTerm | listTerm | tupleTerm | VARIABLE) (OPEN_CT s commaSeparatedFunctors CLOSE)? s;

parenthezedTerm: OPEN_CT term CLOSE;


//lexer grammar mercury;

//http://www.mercury.csse.unimelb.edu.au/information/doc-release/mercury_ref/Tokens.html#Tokens
fragment DIGIT: '0'..'9';

////TODO handle ints, 0b, 0o, 0x, 0'
FLOAT : (DIGIT+ ('.' DIGIT+)? |('.' DIGIT+)) ('E'|'e'('+'|'-')?DIGIT+)?; 


LINE:
    '#' /*INT*/DIGIT+ '\n'
;

STRING:
    ('"' ( '\\' ('a'|'b'|'t'|'n'|'f'|'r'|'u'|'"'|/*'\''|*/'\\') | ~('"' | '\\') )* '"')+
;

NAME:
    (('a'..'z') ('a'..'z'|'A'..'Z'|'_'|'0'..'9')*)/* |
    ('\'' ( '\\' ('a'|'b'|'t'|'n'|'f'|'r'|'u'|'"'|'''|'\\') | ~('\'' | '\\') )* '\'')+*/
	;

VARIABLE:
    ('A'..'Z'|'_') ('a'..'z'|'A'..'Z'|'_'|'0'..'9')*
;

IMPLEMENTATION_DEFINED_LITERAL:
    '$' (('a'..'z') ('a'..'z'|'A'..'Z'|'_'|'0'..'9')*)
;

OPEN_CT:
    '('
;

CLOSE: ')';

OPEN_LIST:'[';
CLOSE_LIST
	:	']';

OPEN_CURLY:'{';
CLOSE_CURLY:'}';

HEAD_TAIL_SEPARATOR:'|';

COMMA:',';

END:'.';

WS         : (' '|'\t'|'\r'|'\n')+;

SL_COMMENT 
	:	 ('%' (~ '\n')*);
	
ML_COMMENT
	:	 '/*' (options {greedy=false;} : .)* '*/' /*{$channel=HIDDEN;}*/;

TERM_END
	:	'.' (WS | SL_COMMENT | ML_COMMENT | EOF);

The https://gist.github.com/3025801/2b48f39914721191f0f3cad9ad2c2520a62bfbf5 version uses an alternative path to handle the different , usages, better . handling. Although the precedence rule 950 still not working well.