1 /**************************************************************************
4 * Author: Maria M. Gutierrez *
5 * Modified by: Kevin Hammond *
6 * Last date revised: December 13 1991. KH. *
7 * Modification: Haskell 1.1 Syntax. *
10 * Description: This file contains the LALR(1) grammar for Haskell. *
12 * Entry Point: module *
14 * Problems: None known. *
17 * LALR(1) Syntax for Haskell 1.2 *
19 **************************************************************************/
31 #include "constants.h"
34 /**********************************************************************
37 * Imported Variables and Functions *
40 **********************************************************************/
42 static BOOLEAN expect_ccurly = FALSE; /* Used to signal that a CCURLY could be inserted here */
45 extern char *input_filename;
46 static char *the_module_name;
47 static maybe module_exports;
50 extern list reverse_list();
53 /* For FN, PREVPATT and SAMEFN macros */
55 extern BOOLEAN samefn[];
56 extern tree prevpatt[];
57 extern short icontexts;
60 extern int hsplineno, hspcolno;
61 extern int modulelineno;
62 extern int startlineno;
65 /**********************************************************************
68 * Fixity and Precedence Declarations *
71 **********************************************************************/
73 static int Fixity = 0, Precedence = 0;
75 char *ineg PROTO((char *));
77 long source_version = 0;
101 /**********************************************************************
104 * These are lexemes. *
107 **********************************************************************/
110 %token VARID CONID QVARID QCONID
111 VARSYM CONSYM QVARSYM QCONSYM
113 %token INTEGER FLOAT CHAR STRING
114 CHARPRIM STRINGPRIM INTPRIM FLOATPRIM
119 /**********************************************************************
125 **********************************************************************/
127 %token OCURLY CCURLY VCCURLY
128 %token COMMA SEMI OBRACK CBRACK
129 %token WILDCARD BQUOTE OPAREN CPAREN
132 /**********************************************************************
135 * Reserved Operators *
138 **********************************************************************/
140 %token DOTDOT DCOLON EQUAL LAMBDA
141 %token VBAR RARROW LARROW
142 %token AT LAZY DARROW
145 /**********************************************************************
148 * Reserved Identifiers *
151 **********************************************************************/
153 %token CASE CLASS DATA
154 %token DEFAULT DERIVING DO
155 %token ELSE IF IMPORT
156 %token IN INFIX INFIXL
157 %token INFIXR INSTANCE LET
158 %token MODULE NEWTYPE OF
159 %token THEN TYPE WHERE
162 %token CCALL CCALL_GC CASM CASM_GC
165 /**********************************************************************
168 * Special symbols/identifiers which need to be recognised *
171 **********************************************************************/
173 %token MINUS BANG PLUS
174 %token AS HIDING QUALIFIED
177 /**********************************************************************
180 * Special Symbols for the Lexer *
183 **********************************************************************/
185 %token INTERFACE_UPRAGMA SPECIALISE_UPRAGMA
186 %token INLINE_UPRAGMA MAGIC_UNFOLDING_UPRAGMA
188 %token SOURCE_UPRAGMA
190 /**********************************************************************
193 * Precedences of the various tokens *
196 **********************************************************************/
201 SCC CASM CCALL CASM_GC CCALL_GC
203 %left VARSYM CONSYM QVARSYM QCONSYM
204 MINUS BQUOTE BANG DARROW PLUS
210 %left OCURLY OBRACK OPAREN
216 /**********************************************************************
219 * Type Declarations *
222 **********************************************************************/
225 %type <ulist> caserest alts alt quals
227 rbinds rbinds1 rpats rpats1 list_exps list_rest
229 constrs constr1 fields
232 pats simple_context simple_context_list
235 impdecls maybeimpdecls impdecl
236 maybefixes fixes fix ops
241 %type <umaybe> maybeexports impspec deriving
243 %type <uliteral> lit_constant
245 %type <utree> exp oexp dexp kexp fexp aexp rbind texps
246 expL oexpL kexpL expLno oexpLno dexpLno kexpLno
247 vallhs funlhs qual leftexp
248 pat cpat bpat apat apatc conpat rpat
249 patk bpatk apatck conpatk
252 %type <uid> MINUS PLUS DARROW AS LAZY
253 VARID CONID VARSYM CONSYM
254 var con varop conop op
255 vark varid varsym varsym_nominus
258 %type <uqid> QVARID QCONID QVARSYM QCONSYM
259 qvarid qconid qvarsym qconsym
260 qvar qcon qvarop qconop qop
261 qvark qconk qtycon qtycls
262 gcon gconk gtycon itycon qop1 qvarop1
265 %type <ubinding> topdecl topdecls letdecls
266 typed datad newtd classd instd defaultd
267 decl decls valdef instdef instdefs
268 maybe_where cbody rinst type_and_maybe_id
270 %type <upbinding> valrhs1 altrest
272 %type <uttype> ctype sigtype sigarrowtype type atype bigatype btype
273 bbtype batype bxtype wierd_atype
274 simple_con_app simple_con_app1 tyvar contype inst_type
276 %type <uconstr> constr constr_after_context field
278 %type <ustring> FLOAT INTEGER INTPRIM
279 FLOATPRIM DOUBLEPRIM CLITLIT
281 %type <uhstring> STRING STRINGPRIM CHAR CHARPRIM
283 %type <uentid> export import
285 %type <ulong> commas importkey get_line_no
287 /**********************************************************************
290 * Start Symbol for the Parser *
293 **********************************************************************/
298 module : modulekey modid maybeexports
300 modulelineno = startlineno;
301 the_module_name = $2;
307 the_module_name = install_literal("Main");
308 module_exports = mknothing();
313 body : ocurly { setstartlineno(); } interface_pragma orestm
314 | vocurly interface_pragma vrestm
317 interface_pragma : /* empty */
318 | INTERFACE_UPRAGMA INTEGER END_UPRAGMA SEMI
320 source_version = atoi($2);
324 orestm : maybeimpdecls maybefixes topdecls ccurly
326 root = mkhmodule(the_module_name,$1,module_exports,
327 $2,$3,source_version,modulelineno);
331 root = mkhmodule(the_module_name,$1,module_exports,
332 Lnil,mknullbind(),source_version,modulelineno);
335 vrestm : maybeimpdecls maybefixes topdecls vccurly
337 root = mkhmodule(the_module_name,$1,module_exports,
338 $2,$3,source_version,modulelineno);
342 root = mkhmodule(the_module_name,$1,module_exports,
343 Lnil,mknullbind(),source_version,modulelineno);
346 maybeexports : /* empty */ { $$ = mknothing(); }
347 | OPAREN export_list CPAREN { $$ = mkjust($2); }
348 | OPAREN export_list COMMA CPAREN { $$ = mkjust($2); }
352 export { $$ = lsing($1); }
353 | export_list COMMA export { $$ = lapp($1, $3); }
356 export : qvar { $$ = mkentid($1); }
357 | gtycon { $$ = mkenttype($1); }
358 | gtycon OPAREN DOTDOT CPAREN { $$ = mkenttypeall($1); }
359 | gtycon OPAREN CPAREN { $$ = mkenttypenamed($1,Lnil); }
360 | gtycon OPAREN enames CPAREN { $$ = mkenttypenamed($1,$3); }
361 | MODULE modid { $$ = mkentmod($2); }
364 enames : ename { $$ = lsing($1); }
365 | enames COMMA ename { $$ = lapp($1,$3); }
372 maybeimpdecls : /* empty */ { $$ = Lnil; }
373 | impdecls SEMI { $$ = $1; }
376 impdecls: impdecl { $$ = $1; }
377 | impdecls SEMI impdecl { $$ = lconc($1,$3); }
381 impdecl : importkey modid impspec
382 { $$ = lsing(mkimport($2,0,mknothing(),$3,$1,startlineno)); }
383 | importkey QUALIFIED modid impspec
384 { $$ = lsing(mkimport($3,1,mknothing(),$4,$1,startlineno)); }
385 | importkey QUALIFIED modid AS modid impspec
386 { $$ = lsing(mkimport($3,1,mkjust($5),$6,$1,startlineno)); }
387 | importkey modid AS modid impspec
388 { $$ = lsing(mkimport($3,1,mkjust($4),$5,$1,startlineno)); }
391 impspec : /* empty */ { $$ = mknothing(); }
392 | OPAREN CPAREN { $$ = mkjust(mkleft(Lnil)); }
393 | OPAREN import_list CPAREN { $$ = mkjust(mkleft($2)); }
394 | OPAREN import_list COMMA CPAREN { $$ = mkjust(mkleft($2)); }
395 | HIDING OPAREN import_list CPAREN { $$ = mkjust(mkright($3)); }
396 | HIDING OPAREN import_list COMMA CPAREN { $$ = mkjust(mkright($3)); }
400 import { $$ = lsing($1); }
401 | import_list COMMA import { $$ = lapp($1, $3); }
404 import : var { $$ = mkentid(mknoqual($1)); }
405 | itycon { $$ = mkenttype($1); }
406 | itycon OPAREN DOTDOT CPAREN { $$ = mkenttypeall($1); }
407 | itycon OPAREN CPAREN { $$ = mkenttypenamed($1,Lnil);}
408 | itycon OPAREN inames CPAREN { $$ = mkenttypenamed($1,$3); }
411 itycon : tycon { $$ = mknoqual($1); }
412 | OBRACK CBRACK { $$ = creategid(NILGID); }
413 | OPAREN CPAREN { $$ = creategid(UNITGID); }
414 | OPAREN commas CPAREN { $$ = creategid($2); }
417 inames : iname { $$ = lsing($1); }
418 | inames COMMA iname { $$ = lapp($1,$3); }
420 iname : var { $$ = mknoqual($1); }
421 | con { $$ = mknoqual($1); }
424 /**********************************************************************
427 * Fixes and Decls etc *
430 **********************************************************************/
432 maybefixes: /* empty */ { $$ = Lnil; }
433 | fixes SEMI { $$ = $1; }
436 fixes : fix { $$ = $1; }
437 | fixes SEMI fix { $$ = lconc($1,$3); }
440 fix : INFIXL INTEGER { Precedence = checkfixity($2); Fixity = INFIXL; }
442 | INFIXR INTEGER { Precedence = checkfixity($2); Fixity = INFIXR; }
444 | INFIX INTEGER { Precedence = checkfixity($2); Fixity = INFIX; }
446 | INFIXL { Fixity = INFIXL; Precedence = 9; }
448 | INFIXR { Fixity = INFIXR; Precedence = 9; }
450 | INFIX { Fixity = INFIX; Precedence = 9; }
454 ops : op { $$ = lsing(mkfixop(mknoqual($1),infixint(Fixity),Precedence,startlineno)); }
455 | ops COMMA op { $$ = lapp($1,mkfixop(mknoqual($3),infixint(Fixity),Precedence,startlineno)); }
459 | topdecls SEMI topdecl
478 topdecl : typed { $$ = $1; FN = NULL; SAMEFN = 0; }
479 | datad { $$ = $1; FN = NULL; SAMEFN = 0; }
480 | newtd { $$ = $1; FN = NULL; SAMEFN = 0; }
481 | classd { $$ = $1; FN = NULL; SAMEFN = 0; }
482 | instd { $$ = $1; FN = NULL; SAMEFN = 0; }
483 | defaultd { $$ = $1; FN = NULL; SAMEFN = 0; }
487 typed : typekey simple_con_app EQUAL type { $$ = mknbind($2,$4,startlineno); }
491 datad : datakey simple_con_app EQUAL constrs deriving
492 { $$ = mktbind(Lnil,$2,$4,$5,startlineno); }
493 | datakey simple_context DARROW simple_con_app EQUAL constrs deriving
494 { $$ = mktbind($2,$4,$6,$7,startlineno); }
497 newtd : newtypekey simple_con_app EQUAL constr1 deriving
498 { $$ = mkntbind(Lnil,$2,$4,$5,startlineno); }
499 | newtypekey simple_context DARROW simple_con_app EQUAL constr1 deriving
500 { $$ = mkntbind($2,$4,$6,$7,startlineno); }
503 deriving: /* empty */ { $$ = mknothing(); }
504 | DERIVING dtyclses { $$ = mkjust($2); }
507 classd : classkey simple_context DARROW simple_con_app1 cbody
508 { $$ = mkcbind($2,$4,$5,startlineno); }
509 | classkey simple_con_app1 cbody
510 { $$ = mkcbind(Lnil,$2,$3,startlineno); }
513 cbody : /* empty */ { $$ = mknullbind(); }
514 | WHERE ocurly decls ccurly { checkorder($3); $$ = $3; }
515 | WHERE vocurly decls vccurly { checkorder($3); $$ = $3; }
518 instd : instkey inst_type rinst { $$ = mkibind($2,$3,startlineno); }
522 inst_type : type DARROW type { is_context_format( $3, 0 ); /* Check the instance head */
523 $$ = mkcontext(type2context($1),$3); }
524 | type { is_context_format( $1, 0 ); /* Check the instance head */
529 rinst : /* empty */ { $$ = mknullbind(); }
530 | WHERE ocurly instdefs ccurly { $$ = $3; }
531 | WHERE vocurly instdefs vccurly { $$ = $3; }
534 defaultd: defaultkey OPAREN types CPAREN { $$ = mkdbind($3,startlineno); }
535 | defaultkey OPAREN CPAREN { $$ = mkdbind(Lnil,startlineno); }
552 Note: if there is an iclasop_pragma here, then we must be
553 doing a class-op in an interface -- unless the user is up
554 to real mischief (ugly, but likely to work).
557 decl : qvarsk DCOLON sigtype
558 { $$ = mksbind($1,$3,startlineno);
559 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
562 /* User-specified pragmas come in as "signatures"...
563 They are similar in that they can appear anywhere in the module,
564 and have to be "joined up" with their related entity.
566 Have left out the case specialising to an overloaded type.
567 Let's get real, OK? (WDP)
569 | SPECIALISE_UPRAGMA qvark DCOLON types_and_maybe_ids END_UPRAGMA
571 $$ = mkvspec_uprag($2, $4, startlineno);
572 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
575 | SPECIALISE_UPRAGMA INSTANCE gtycon atype END_UPRAGMA
577 $$ = mkispec_uprag($3, $4, startlineno);
578 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
581 | SPECIALISE_UPRAGMA DATA gtycon atypes END_UPRAGMA
583 $$ = mkdspec_uprag($3, $4, startlineno);
584 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
587 | INLINE_UPRAGMA qvark END_UPRAGMA
589 $$ = mkinline_uprag($2, startlineno);
590 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
593 | MAGIC_UNFOLDING_UPRAGMA qvark vark END_UPRAGMA
595 $$ = mkmagicuf_uprag($2, $3, startlineno);
596 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
599 /* end of user-specified pragmas */
602 | /* empty */ { $$ = mknullbind(); PREVPATT = NULL; FN = NULL; SAMEFN = 0; }
605 qvarsk : qvark COMMA qvars_list { $$ = mklcons($1,$3); }
606 | qvark { $$ = lsing($1); }
609 qvars_list: qvar { $$ = lsing($1); }
610 | qvars_list COMMA qvar { $$ = lapp($1,$3); }
613 types_and_maybe_ids :
614 type_and_maybe_id { $$ = lsing($1); }
615 | types_and_maybe_ids COMMA type_and_maybe_id { $$ = lapp($1,$3); }
619 type { $$ = mkvspec_ty_and_id($1,mknothing()); }
620 | type EQUAL qvark { $$ = mkvspec_ty_and_id($1,mkjust($3)); }
623 /**********************************************************************
629 **********************************************************************/
631 /* "DCOLON context => type" vs "DCOLON type" is a problem,
632 because you can't distinguish between
634 foo :: (Baz a, Baz a)
635 bar :: (Baz a, Baz a) => [a] -> [a] -> [a]
637 with one token of lookahead. The HACK is to have "DCOLON ttype"
638 [tuple type] in the first case, then check that it has the right
639 form C a, or (C1 a, C2 b, ... Cn z) and convert it into a
643 /* A sigtype is a rank 2 type; it can have for-alls as function args:
644 f :: All a => (All b => ...) -> Int
646 sigtype : type DARROW sigarrowtype { $$ = mkcontext(type2context($1),$3); }
650 sigarrowtype : bigatype RARROW sigarrowtype { $$ = mktfun($1,$3); }
651 | btype RARROW sigarrowtype { $$ = mktfun($1,$3); }
655 /* A "big" atype can be a forall-type in brackets. */
656 bigatype: OPAREN type DARROW type CPAREN { $$ = mkcontext(type2context($2),$4); }
659 /* 1 S/R conflict at DARROW -> shift */
660 ctype : type DARROW type { $$ = mkcontext(type2context($1),$3); }
664 /* 1 S/R conflict at RARROW -> shift */
665 type : btype RARROW type { $$ = mktfun($1,$3); }
669 btype : btype atype { $$ = mktapp($1,$2); }
673 atype : gtycon { $$ = mktname($1); }
675 | OPAREN type COMMA types CPAREN { $$ = mkttuple(mklcons($2,$4)); }
676 | OBRACK type CBRACK { $$ = mktllist($2); }
677 | OPAREN type CPAREN { $$ = $2; }
681 | OPAREN RARROW CPAREN { $$ = creategid(ARROWGID); }
682 | OBRACK CBRACK { $$ = creategid(NILGID); }
683 | OPAREN CPAREN { $$ = creategid(UNITGID); }
684 | OPAREN commas CPAREN { $$ = creategid($2); }
687 atypes : atype { $$ = lsing($1); }
688 | atypes atype { $$ = lapp($1,$2); }
691 types : type { $$ = lsing($1); }
692 | types COMMA type { $$ = lapp($1,$3); }
695 commas : COMMA { $$ = 1; }
696 | commas COMMA { $$ = $1 + 1; }
699 /**********************************************************************
702 * Declaration stuff *
705 **********************************************************************/
707 /* C a b c, where a,b,c are type variables */
708 /* C can be a class or tycon */
709 simple_con_app: gtycon { $$ = mktname($1); }
710 | simple_con_app1 { $$ = $1; }
713 simple_con_app1: gtycon tyvar { $$ = mktapp(mktname($1),$2); }
714 | simple_con_app tyvar { $$ = mktapp($1, $2); }
717 simple_context : OPAREN simple_context_list CPAREN { $$ = $2; }
718 | simple_con_app1 { $$ = lsing($1); }
721 simple_context_list: simple_con_app1 { $$ = lsing($1); }
722 | simple_context_list COMMA simple_con_app1 { $$ = lapp($1,$3); }
725 constrs : constr { $$ = lsing($1); }
726 | constrs VBAR constr { $$ = lapp($1,$3); }
729 constr : constr_after_context
730 | type DARROW constr_after_context { $$ = mkconstrcxt ( type2context($1), $3 ); }
733 constr_after_context :
735 /* We have to parse the constructor application as a *type*, else we get
736 into terrible ambiguity problems. Consider the difference between
738 data T = S Int Int Int `R` Int
740 data T = S Int Int Int
742 It isn't till we get to the operator that we discover that the "S" is
743 part of a type in the first, but part of a constructor application in the
747 /* Con !Int (Tree a) */
748 contype { qid tyc; list tys;
749 splittyconapp($1, &tyc, &tys);
750 $$ = mkconstrpre(tyc,tys,hsplineno); }
752 /* !Int `Con` Tree a */
753 | bbtype qconop bbtype { $$ = mkconstrinf($1,$2,$3,hsplineno); }
755 /* (::) (Tree a) Int */
756 | OPAREN qconsym CPAREN batypes { $$ = mkconstrpre($2,$4,hsplineno); }
758 /* Con { op1 :: Int } */
759 | qtycon OCURLY fields CCURLY { $$ = mkconstrrec($1,$3,hsplineno); }
760 | OPAREN qconsym CPAREN OCURLY fields CCURLY { $$ = mkconstrrec($2,$5,hsplineno); }
762 /* 1 S/R conflict on OCURLY -> shift */
765 /* contype has to reduce to a btype unless there are !'s, so that
766 we don't get reduce/reduce conflicts with the second production of constr.
767 But as soon as we see a ! we must switch to using bxtype. */
769 contype : btype { $$ = $1; }
770 | bxtype { $$ = $1; }
773 /* S !Int Bool; at least one ! */
774 bxtype : btype wierd_atype { $$ = mktapp($1, $2); }
775 | bxtype batype { $$ = mktapp($1, $2); }
778 bbtype : btype { $$ = $1; }
779 | wierd_atype { $$ = $1; }
782 batype : atype { $$ = $1; }
783 | wierd_atype { $$ = $1; }
786 /* A wierd atype is one that isn't a regular atype;
787 it starts with a "!", or with a forall. */
788 wierd_atype : BANG bigatype { $$ = mktbang( $2 ); }
789 | BANG atype { $$ = mktbang( $2 ); }
793 batypes : { $$ = Lnil; }
794 | batypes batype { $$ = lapp($1,$2); }
798 fields : field { $$ = lsing($1); }
799 | fields COMMA field { $$ = lapp($1,$3); }
802 field : qvars_list DCOLON ctype { $$ = mkfield($1,$3); }
803 | qvars_list DCOLON BANG atype { $$ = mkfield($1,mktbang($4)); }
804 | qvars_list DCOLON BANG bigatype { $$ = mkfield($1,mktbang($4)); }
807 constr1 : gtycon atype { $$ = lsing(mkconstrnew($1,$2,hsplineno)); }
811 dtyclses: OPAREN dtycls_list CPAREN { $$ = $2; }
812 | OPAREN CPAREN { $$ = Lnil; }
813 | qtycls { $$ = lsing($1); }
816 dtycls_list: qtycls { $$ = lsing($1); }
817 | dtycls_list COMMA qtycls { $$ = lapp($1,$3); }
820 instdefs : /* empty */ { $$ = mknullbind(); }
821 | instdef { $$ = $1; }
822 | instdefs SEMI instdef
834 /* instdef: same as valdef, except certain user-pragmas may appear */
836 SPECIALISE_UPRAGMA qvark DCOLON types_and_maybe_ids END_UPRAGMA
838 $$ = mkvspec_uprag($2, $4, startlineno);
839 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
842 | INLINE_UPRAGMA qvark END_UPRAGMA
844 $$ = mkinline_uprag($2, startlineno);
845 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
848 | MAGIC_UNFOLDING_UPRAGMA qvark vark END_UPRAGMA
850 $$ = mkmagicuf_uprag($2, $3, startlineno);
851 PREVPATT = NULL; FN = NULL; SAMEFN = 0;
861 tree fn = function($1);
864 if(ttree(fn) == ident)
866 qid fun_id = gident((struct Sident *) fn);
871 else if (ttree(fn) == infixap)
873 qid fun_id = ginffun((struct Sinfixap *) fn);
880 printf("%u\n",startlineno);
882 fprintf(stderr,"%u\tvaldef\n",startlineno);
889 if ( lhs_is_patt($1) )
891 $$ = mkpbind($4, $3);
896 $$ = mkfbind($4, $3);
902 get_line_no : { $$ = startlineno; }
905 vallhs : patk { $$ = $1; }
906 | patk qvarop pat { $$ = mkinfixap($2,$1,$3); }
907 | funlhs { $$ = $1; }
910 funlhs : qvark apat { $$ = mkap(mkident($1),$2); }
911 | funlhs apat { $$ = mkap($1,$2); }
915 valrhs : valrhs1 maybe_where { $$ = lsing(createpat($1, $2)); }
918 valrhs1 : gdrhs { $$ = mkpguards($1); }
919 | EQUAL exp { $$ = mkpnoguards($2); }
922 gdrhs : gd EQUAL exp { $$ = lsing(mkpgdexp($1,$3)); }
923 | gd EQUAL exp gdrhs { $$ = mklcons(mkpgdexp($1,$3),$4); }
927 WHERE ocurly decls ccurly { $$ = $3; }
928 | WHERE vocurly decls vccurly { $$ = $3; }
929 /* A where containing no decls is OK */
930 | WHERE SEMI { $$ = mknullbind(); }
931 | /* empty */ { $$ = mknullbind(); }
934 gd : VBAR quals { $$ = $2; }
938 /**********************************************************************
944 **********************************************************************/
946 exp : oexp DCOLON ctype { $$ = mkrestr($1,$3); }
951 Operators must be left-associative at the same precedence for
952 precedence parsing to work.
954 /* 8 S/R conflicts on qop -> shift */
955 oexp : oexp qop oexp %prec MINUS { $$ = mkinfixap($2,$1,$3); }
960 This comes here because of the funny precedence rules concerning
963 dexp : MINUS kexp { $$ = mknegate($2); }
968 We need to factor out a leading let expression so we can set
969 inpat=TRUE when parsing (non let) expressions inside stmts and quals
971 expLno : oexpLno DCOLON ctype { $$ = mkrestr($1,$3); }
974 oexpLno : oexpLno qop oexp %prec MINUS { $$ = mkinfixap($2,$1,$3); }
977 dexpLno : MINUS kexp { $$ = mknegate($2); }
981 expL : oexpL DCOLON ctype { $$ = mkrestr($1,$3); }
984 oexpL : oexpL qop oexp %prec MINUS { $$ = mkinfixap($2,$1,$3); }
989 let/if/lambda/case have higher precedence than infix operators.
996 /* kexpL = a let expression */
997 kexpL : letdecls IN exp { $$ = mklet($1,$3); }
1000 /* kexpLno = any other expression more tightly binding than operator application */
1002 { hsincindent(); /* push new context for FN = NULL; */
1003 FN = NULL; /* not actually concerned about indenting */
1004 $<ulong>$ = hsplineno; /* remember current line number */
1009 RARROW exp /* lambda abstraction */
1011 $$ = mklambda($3, $6, $<ulong>2);
1015 | IF {$<ulong>$ = hsplineno;}
1016 exp THEN exp ELSE exp { $$ = mkife($3,$5,$7,$<ulong>2); }
1018 /* Case Expression */
1019 | CASE {$<ulong>$ = hsplineno;}
1020 exp OF caserest { $$ = mkcasee($3,$5,$<ulong>2); }
1023 | DO {$<ulong>$ = hsplineno;}
1024 dorest { $$ = mkdoe($3,$<ulong>2); }
1026 /* CCALL/CASM Expression */
1027 | CCALL ccallid cexps { $$ = mkccall($2,install_literal("n"),$3); }
1028 | CCALL ccallid { $$ = mkccall($2,install_literal("n"),Lnil); }
1029 | CCALL_GC ccallid cexps { $$ = mkccall($2,install_literal("p"),$3); }
1030 | CCALL_GC ccallid { $$ = mkccall($2,install_literal("p"),Lnil); }
1031 | CASM CLITLIT cexps { $$ = mkccall($2,install_literal("N"),$3); }
1032 | CASM CLITLIT { $$ = mkccall($2,install_literal("N"),Lnil); }
1033 | CASM_GC CLITLIT cexps { $$ = mkccall($2,install_literal("P"),$3); }
1034 | CASM_GC CLITLIT { $$ = mkccall($2,install_literal("P"),Lnil); }
1036 /* SCC Expression */
1041 "\"%s\":%d: _scc_ (`set [profiling] cost centre') ignored\n",
1042 input_filename, hsplineno);
1044 $$ = mkpar($3); /* Note the mkpar(). If we don't have it, then
1045 (x >> _scc_ y >> z) parses as (x >> (y >> z)),
1046 right associated. But the precedence reorganiser expects
1047 the parser to *left* associate all operators unless there
1048 are explicit parens. The _scc_ acts like an explicit paren,
1049 so if we omit it we'd better add explicit parens instead. */
1057 fexp : fexp aexp { $$ = mkap($1,$2); }
1061 /* simple expressions */
1062 aexp : qvar { $$ = mkident($1); }
1063 | gcon { $$ = mkident($1); }
1064 | lit_constant { $$ = mklit($1); }
1065 | OPAREN exp CPAREN { $$ = mkpar($2); } /* mkpar: stop infix parsing at ()'s */
1066 | qcon OCURLY rbinds CCURLY { $$ = mkrecord($1,$3); } /* 1 S/R conflict on OCURLY -> shift */
1067 | OBRACK list_exps CBRACK { $$ = mkllist($2); }
1068 | OPAREN exp COMMA texps CPAREN { if (ttree($4) == tuple)
1069 $$ = mktuple(mklcons($2, gtuplelist((struct Stuple *) $4)));
1071 $$ = mktuple(ldub($2, $4)); }
1073 /* only in expressions ... */
1074 | aexp OCURLY rbinds1 CCURLY { $$ = mkrupdate($1,$3); }
1075 | OBRACK exp VBAR quals CBRACK { $$ = mkcomprh($2,$4); }
1076 | OBRACK exp COMMA exp DOTDOT exp CBRACK {$$= mkeenum($2,mkjust($4),mkjust($6)); }
1077 | OBRACK exp COMMA exp DOTDOT CBRACK { $$ = mkeenum($2,mkjust($4),mknothing()); }
1078 | OBRACK exp DOTDOT exp CBRACK { $$ = mkeenum($2,mknothing(),mkjust($4)); }
1079 | OBRACK exp DOTDOT CBRACK { $$ = mkeenum($2,mknothing(),mknothing()); }
1080 | OPAREN oexp qop CPAREN { $$ = mklsection($2,$3); }
1081 | OPAREN qop1 oexp CPAREN { $$ = mkrsection($2,$3); }
1083 /* only in patterns ... */
1084 /* these add 2 S/R conflict with with aexp . OCURLY rbinds CCURLY */
1085 | qvar AT aexp { $$ = mkas($1,$3); }
1086 | LAZY aexp { $$ = mklazyp($2); }
1087 | WILDCARD { $$ = mkwildp(); }
1090 /* ccall arguments */
1091 cexps : cexps aexp { $$ = lapp($1,$2); }
1092 | aexp { $$ = lsing($1); }
1095 caserest: ocurly alts ccurly { $$ = $2; }
1096 | vocurly alts vccurly { $$ = $2; }
1098 dorest : ocurly stmts ccurly { checkdostmts($2); $$ = $2; }
1099 | vocurly stmts vccurly { checkdostmts($2); $$ = $2; }
1102 rbinds : /* empty */ { $$ = Lnil; }
1106 rbinds1 : rbind { $$ = lsing($1); }
1107 | rbinds1 COMMA rbind { $$ = lapp($1,$3); }
1110 rbind : qvar { $$ = mkrbind($1,mknothing()); }
1111 | qvar EQUAL exp { $$ = mkrbind($1,mkjust($3)); }
1114 texps : exp { $$ = mkpar($1); } /* mkpar: so we don't flatten last element in tuple */
1116 { if (ttree($3) == tuple)
1117 $$ = mktuple(mklcons($1, gtuplelist((struct Stuple *) $3)));
1118 else if (ttree($3) == par)
1119 $$ = mktuple(ldub($1, gpare((struct Spar *) $3)));
1121 hsperror("hsparser:texps: panic");
1123 /* right recursion? WDP */
1127 exp { $$ = lsing($1); }
1128 | exp COMMA exp { $$ = mklcons( $1, lsing($3) ); }
1129 | exp COMMA exp COMMA list_rest { $$ = mklcons( $1, mklcons( $3, reverse_list( $5 ))); }
1132 /* Use left recusion for list_rest, because we sometimes get programs with
1133 very long explicit lists. */
1134 list_rest : exp { $$ = lsing($1); }
1135 | list_rest COMMA exp { $$ = mklcons( $3, $1 ); }
1139 exp { $$ = lsing($1); }
1140 | exp COMMA list_exps { $$ = mklcons($1, $3); }
1142 /* right recursion? (WDP)
1144 It has to be this way, though, otherwise you
1145 may do the wrong thing to distinguish between...
1147 [ e1 , e2 .. ] -- an enumeration ...
1148 [ e1 , e2 , e3 ] -- a list
1150 (In fact, if you change the grammar and throw yacc/bison
1151 at it, it *will* do the wrong thing [WDP 94/06])
1154 letdecls: LET ocurly decls ccurly { $$ = $3; }
1155 | LET vocurly decls vccurly { $$ = $3; }
1158 quals : qual { $$ = lsing($1); }
1159 | quals COMMA qual { $$ = lapp($1,$3); }
1162 qual : letdecls { $$ = mkseqlet($1); }
1166 expORpat(LEGIT_EXPR,$1);
1169 expORpat(LEGIT_PATT,$1);
1175 alts : alt { $$ = $1; }
1176 | alts SEMI alt { $$ = lconc($1,$3); }
1179 alt : pat { PREVPATT = $1; } altrest { expORpat(LEGIT_PATT,$1); $$ = lsing($3); PREVPATT = NULL; }
1180 | /* empty */ { $$ = Lnil; }
1183 altrest : gdpat maybe_where { $$ = createpat(mkpguards($1), $2); }
1184 | RARROW exp maybe_where { $$ = createpat(mkpnoguards($2),$3); }
1187 gdpat : gd RARROW exp { $$ = lsing(mkpgdexp($1,$3)); }
1188 | gd RARROW exp gdpat { $$ = mklcons(mkpgdexp($1,$3),$4); }
1191 stmts : stmt { $$ = $1; }
1192 | stmts SEMI stmt { $$ = lconc($1,$3); }
1195 stmt : /* empty */ { $$ = Lnil; }
1196 | letdecls { $$ = lsing(mkseqlet($1)); }
1197 | expL { $$ = lsing(mkdoexp($1,hsplineno)); }
1200 expORpat(LEGIT_EXPR,$1);
1201 $$ = lsing(mkdoexp($1,endlineno));
1203 expORpat(LEGIT_PATT,$1);
1204 $$ = lsing(mkdobind($1,$2,endlineno));
1209 leftexp : LARROW exp { $$ = $2; }
1210 | /* empty */ { $$ = NULL; }
1213 /**********************************************************************
1219 **********************************************************************/
1221 pat : qvar PLUS INTEGER { $$ = mkplusp($1, mkinteger($3)); }
1225 cpat : cpat qconop bpat { $$ = mkinfixap($2,$1,$3); }
1231 | qcon OCURLY rpats CCURLY { $$ = mkrecord($1,$3); }
1232 | MINUS INTEGER { $$ = mknegate(mklit(mkinteger($2))); }
1233 | MINUS FLOAT { $$ = mknegate(mklit(mkfloatr($2))); }
1236 conpat : gcon { $$ = mkident($1); }
1237 | conpat apat { $$ = mkap($1,$2); }
1240 apat : gcon { $$ = mkident($1); }
1241 | qcon OCURLY rpats CCURLY { $$ = mkrecord($1,$3); }
1245 apatc : qvar { $$ = mkident($1); }
1246 | qvar AT apat { $$ = mkas($1,$3); }
1247 | lit_constant { $$ = mklit($1); }
1248 | WILDCARD { $$ = mkwildp(); }
1249 | OPAREN pat CPAREN { $$ = mkpar($2); }
1250 | OPAREN pat COMMA pats CPAREN { $$ = mktuple(mklcons($2,$4)); }
1251 | OBRACK pats CBRACK { $$ = mkllist($2); }
1252 | LAZY apat { $$ = mklazyp($2); }
1256 INTEGER { $$ = mkinteger($1); }
1257 | FLOAT { $$ = mkfloatr($1); }
1258 | CHAR { $$ = mkcharr($1); }
1259 | STRING { $$ = mkstring($1); }
1260 | CHARPRIM { $$ = mkcharprim($1); }
1261 | STRINGPRIM { $$ = mkstringprim($1); }
1262 | INTPRIM { $$ = mkintprim($1); }
1263 | FLOATPRIM { $$ = mkfloatprim($1); }
1264 | DOUBLEPRIM { $$ = mkdoubleprim($1); }
1265 | CLITLIT /* yurble yurble */ { $$ = mkclitlit($1); }
1268 lampats : apat lampats { $$ = mklcons($1,$2); }
1269 | apat { $$ = lsing($1); }
1270 /* right recursion? (WDP) */
1273 pats : pat COMMA pats { $$ = mklcons($1, $3); }
1274 | pat { $$ = lsing($1); }
1275 /* right recursion? (WDP) */
1278 rpats : /* empty */ { $$ = Lnil; }
1282 rpats1 : rpat { $$ = lsing($1); }
1283 | rpats1 COMMA rpat { $$ = lapp($1,$3); }
1286 rpat : qvar { $$ = mkrbind($1,mknothing()); }
1287 | qvar EQUAL pat { $$ = mkrbind($1,mkjust($3)); }
1291 patk : patk qconop bpat { $$ = mkinfixap($2,$1,$3); }
1297 | qconk OCURLY rpats CCURLY { $$ = mkrecord($1,$3); }
1298 | minuskey INTEGER { $$ = mknegate(mklit(mkinteger($2))); }
1299 | minuskey FLOAT { $$ = mknegate(mklit(mkfloatr($2))); }
1302 conpatk : gconk { $$ = mkident($1); }
1303 | conpatk apat { $$ = mkap($1,$2); }
1306 apatck : qvark { $$ = mkident($1); }
1307 | qvark AT apat { $$ = mkas($1,$3); }
1308 | lit_constant { $$ = mklit($1); setstartlineno(); }
1309 | WILDCARD { $$ = mkwildp(); setstartlineno(); }
1310 | oparenkey pat CPAREN { $$ = mkpar($2); }
1311 | oparenkey pat COMMA pats CPAREN { $$ = mktuple(mklcons($2,$4)); }
1312 | obrackkey pats CBRACK { $$ = mkllist($2); }
1313 | lazykey apat { $$ = mklazyp($2); }
1318 | OBRACK CBRACK { $$ = creategid(NILGID); }
1319 | OPAREN CPAREN { $$ = creategid(UNITGID); }
1320 | OPAREN commas CPAREN { $$ = creategid($2); }
1324 | obrackkey CBRACK { $$ = creategid(NILGID); }
1325 | oparenkey CPAREN { $$ = creategid(UNITGID); }
1326 | oparenkey commas CPAREN { $$ = creategid($2); }
1329 /**********************************************************************
1332 * Keywords which record the line start *
1335 **********************************************************************/
1337 importkey: IMPORT { setstartlineno(); $$ = 0; }
1338 | IMPORT SOURCE_UPRAGMA { setstartlineno(); $$ = 1; }
1341 datakey : DATA { setstartlineno();
1344 printf("%u\n",startlineno);
1346 fprintf(stderr,"%u\tdata\n",startlineno);
1351 typekey : TYPE { setstartlineno();
1354 printf("%u\n",startlineno);
1356 fprintf(stderr,"%u\ttype\n",startlineno);
1361 newtypekey : NEWTYPE { setstartlineno();
1364 printf("%u\n",startlineno);
1366 fprintf(stderr,"%u\tnewtype\n",startlineno);
1371 instkey : INSTANCE { setstartlineno();
1374 printf("%u\n",startlineno);
1377 fprintf(stderr,"%u\tinstance\n",startlineno);
1382 defaultkey: DEFAULT { setstartlineno(); }
1385 classkey: CLASS { setstartlineno();
1388 printf("%u\n",startlineno);
1390 fprintf(stderr,"%u\tclass\n",startlineno);
1395 modulekey: MODULE { setstartlineno();
1398 printf("%u\n",startlineno);
1400 fprintf(stderr,"%u\tmodule\n",startlineno);
1405 oparenkey: OPAREN { setstartlineno(); }
1408 obrackkey: OBRACK { setstartlineno(); }
1411 lazykey : LAZY { setstartlineno(); }
1414 minuskey: MINUS { setstartlineno(); }
1418 /**********************************************************************
1421 * Basic qualified/unqualified ids/ops *
1424 **********************************************************************/
1427 | OPAREN qvarsym CPAREN { $$ = $2; }
1430 | OPAREN qconsym CPAREN { $$ = $2; }
1433 | BQUOTE qvarid BQUOTE { $$ = $2; }
1436 | BQUOTE qconid BQUOTE { $$ = $2; }
1442 /* Non "-" op, used in right sections */
1447 /* Non "-" varop, used in right sections */
1449 | varsym_nominus { $$ = mknoqual($1); }
1450 | BQUOTE qvarid BQUOTE { $$ = $2; }
1455 | OPAREN varsym CPAREN { $$ = $2; }
1457 con : tycon /* using tycon removes conflicts */
1458 | OPAREN CONSYM CPAREN { $$ = $2; }
1461 | BQUOTE varid BQUOTE { $$ = $2; }
1464 | BQUOTE CONID BQUOTE { $$ = $2; }
1470 qvark : qvarid { setstartlineno(); $$ = $1; }
1471 | oparenkey qvarsym CPAREN { $$ = $2; }
1473 qconk : qconid { setstartlineno(); $$ = $1; }
1474 | oparenkey qconsym CPAREN { $$ = $2; }
1476 vark : varid { setstartlineno(); $$ = $1; }
1477 | oparenkey varsym CPAREN { $$ = $2; }
1481 | varid { $$ = mknoqual($1); }
1484 | varsym { $$ = mknoqual($1); }
1487 | tycon { $$ = mknoqual($1); } /* using tycon removes conflicts */
1490 | CONSYM { $$ = mknoqual($1); }
1493 | tycon { $$ = mknoqual($1); } /* using tycon removes conflicts */
1496 | tycon { $$ = mknoqual($1); } /* using tycon removes conflicts */
1499 varsym : varsym_nominus
1500 | MINUS { $$ = install_literal("-"); }
1503 /* PLUS, BANG are valid varsyms */
1504 varsym_nominus : VARSYM
1505 | PLUS { $$ = install_literal("+"); }
1506 | BANG { $$ = install_literal("!"); }
1509 /* AS HIDING QUALIFIED are valid varids */
1511 | AS { $$ = install_literal("as"); }
1512 | HIDING { $$ = install_literal("hiding"); }
1513 | QUALIFIED { $$ = install_literal("qualified"); }
1521 tyvar : varid { $$ = mknamedtvar(mknoqual($1)); }
1529 tyvar_list: tyvar { $$ = lsing($1); }
1530 | tyvar_list COMMA tyvar { $$ = lapp($1,$3); }
1534 /**********************************************************************
1537 * Stuff to do with layout *
1540 **********************************************************************/
1542 ocurly : layout OCURLY { hsincindent(); }
1544 vocurly : layout { hssetindent(); }
1547 layout : { hsindentoff(); }
1553 FN = NULL; SAMEFN = 0; PREVPATT = NULL;
1558 vccurly : { expect_ccurly = 1; } vccurly1 { expect_ccurly = 0; }
1564 FN = NULL; SAMEFN = 0; PREVPATT = NULL;
1570 FN = NULL; SAMEFN = 0; PREVPATT = NULL;
1577 /**********************************************************************
1579 * Error Processing and Reporting *
1581 * (This stuff is here in case we want to use Yacc macros and such.) *
1583 **********************************************************************/
1591 hsperror("pattern syntax used in expression");
1595 /* The parser calls "hsperror" when it sees a
1596 `report this and die' error. It sets the stage
1597 and calls "yyerror".
1599 There should be no direct calls in the parser to
1600 "yyerror", except for the one from "hsperror". Thus,
1601 the only other calls will be from the error productions
1602 introduced by yacc/bison/whatever.
1604 We need to be able to recognise the from-error-production
1605 case, because we sometimes want to say, "Oh, never mind",
1606 because the layout rule kicks into action and may save
1610 static BOOLEAN error_and_I_mean_it = FALSE;
1616 error_and_I_mean_it = TRUE;
1620 extern char *yytext;
1627 /* We want to be able to distinguish 'error'-raised yyerrors
1628 from yyerrors explicitly coded by the parser hacker.
1630 if (expect_ccurly && ! error_and_I_mean_it ) {
1634 fprintf(stderr, "%s:%d:%d: %s on input: ",
1635 input_filename, hsplineno, hspcolno + 1, s);
1637 if (yyleng == 1 && *yytext == '\0')
1638 fprintf(stderr, "<EOF>");
1642 format_string(stderr, (unsigned char *) yytext, yyleng);
1645 fputc('\n', stderr);
1647 /* a common problem */
1648 if (strcmp(yytext, "#") == 0)
1649 fprintf(stderr, "\t(Perhaps you forgot a `-cpp' or `-fglasgow-exts' flag?)\n");
1656 format_string(fp, s, len)
1663 case '\0': fputs("\\NUL", fp); break;
1664 case '\007': fputs("\\a", fp); break;
1665 case '\010': fputs("\\b", fp); break;
1666 case '\011': fputs("\\t", fp); break;
1667 case '\012': fputs("\\n", fp); break;
1668 case '\013': fputs("\\v", fp); break;
1669 case '\014': fputs("\\f", fp); break;
1670 case '\015': fputs("\\r", fp); break;
1671 case '\033': fputs("\\ESC", fp); break;
1672 case '\034': fputs("\\FS", fp); break;
1673 case '\035': fputs("\\GS", fp); break;
1674 case '\036': fputs("\\RS", fp); break;
1675 case '\037': fputs("\\US", fp); break;
1676 case '\177': fputs("\\DEL", fp); break;
1681 fprintf(fp, "\\^%c", *s + '@');