1 rizwank 1.1 %{
  2             /* 								-*- c -*-
  3              * Grammar for states.
  4              * Copyright (c) 1997-1998 Markku Rossi.
  5              *
  6              * Author: Markku Rossi <mtr@iki.fi>
  7              */
  8             
  9             /*
 10              * This file is part of GNU enscript.
 11              *
 12              * This program is free software; you can redistribute it and/or modify
 13              * it under the terms of the GNU General Public License as published by
 14              * the Free Software Foundation; either version 2, or (at your option)
 15              * any later version.
 16              *
 17              * This program is distributed in the hope that it will be useful,
 18              * but WITHOUT ANY WARRANTY; without even the implied warranty of
 19              * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 20              * GNU General Public License for more details.
 21              *
 22 rizwank 1.1  * You should have received a copy of the GNU General Public License
 23              * along with this program; see the file COPYING.  If not, write to
 24              * the Free Software Foundation, 59 Temple Place - Suite 330,
 25              * Boston, MA 02111-1307, USA.
 26              */
 27             
 28             /*
 29              * $Id: gram.y,v 1.9 1998/10/21 08:45:22 mtr Exp $
 30              */
 31             
 32             #include "defs.h"
 33             %}
 34             
 35             %union
 36             {
 37               List *lst;
 38               Node *node;
 39               Cons *cons;
 40               Stmt *stmt;
 41               Expr *expr;
 42             }
 43 rizwank 1.1 
 44             %token <node> tSYMBOL tREGEXP tSTRING tINTEGER tREAL
 45             %token tSUB tSTATE tSTART tSTARTRULES tNAMERULES tBEGIN tEND tRETURN tIF tELSE
 46             %token tLOCAL tWHILE tFOR tEXTENDS
 47             
 48             %right '=' tADDASSIGN tSUBASSIGN tMULASSIGN tDIVASSIGN
 49             %right '?' ':'
 50             %left tOR
 51             %left tAND
 52             %left tEQ tNE
 53             %left '<' '>' tGE tLE
 54             %left '+' '-'
 55             %left '*' tDIV
 56             %right '!' tPLUSPLUS tMINUSMINUS
 57             %left '[' ']'
 58             
 59             %type <lst> regexp_sym_list symbol_list rest_symbol_list staterules
 60             %type <lst> stmt_list expr_list rest_expr_list locals locals_rest
 61             %type <stmt> stmt
 62             %type <expr> expr cond_expr
 63             %type <cons> staterule local_def
 64 rizwank 1.1 
 65             %%
 66             
 67             file	: /* empty */
 68             	| file toplevel
 69             	;
 70             
 71             toplevel : tSTART '{' stmt_list '}'	{ start_stmts = $3; }
 72             	| tSTARTRULES '{' regexp_sym_list '}'
 73             					{ startrules = $3; }
 74             	| tNAMERULES '{' regexp_sym_list '}'
 75             					{ namerules = $3; }
 76             	| tSTATE tSYMBOL '{' staterules '}'
 77             					{ define_state ($2, NULL, $4); }
 78             	| tSTATE tSYMBOL tEXTENDS tSYMBOL '{' staterules '}'
 79             					{ define_state ($2, $4, $6); }
 80             	| stmt				{ list_append (global_stmts, $1); }
 81             	;
 82             
 83             regexp_sym_list : /* empty */ 		{ $$ = list (); }
 84             	| regexp_sym_list tREGEXP tSYMBOL ';'
 85 rizwank 1.1 					{ list_append ($1, cons ($2, $3)); }
 86             	;
 87             
 88             staterules : /* empty */ 		{ $$ = list (); }
 89             	| staterules staterule		{ list_append ($1, $2); }
 90             
 91             staterule : tBEGIN '{' stmt_list '}' 	{ $$ = cons (RULE_BEGIN, $3); }
 92             	| tEND '{' stmt_list '}' 	{ $$ = cons (RULE_END, $3); }
 93             	| tREGEXP '{' stmt_list '}'	{ $$ = cons ($1, $3); }
 94             	| tSYMBOL '{' stmt_list '}'	{ $$ = cons ($1, $3); }
 95             	;
 96             
 97             symbol_list : /* empty */		{ $$ = list (); }
 98             	| rest_symbol_list	 	{ $$ = $1; }
 99             	;
100             
101             rest_symbol_list : tSYMBOL		{ $$ = list (); list_append ($$, $1); }
102             	| rest_symbol_list ',' tSYMBOL 	{ list_append ($1, $3); }
103             	;
104             
105             locals	: /* empty */			{ $$ = list (); }
106 rizwank 1.1 	| tLOCAL locals_rest ';'	{ $$ = $2; }
107             	;
108             
109             locals_rest : local_def			{ $$ = list (); list_append ($$, $1); }
110             	| locals_rest ',' local_def	{ list_append ($1, $3); }
111             	;
112             
113             local_def : tSYMBOL			{ $$ = cons ($1, NULL); }
114             	| tSYMBOL '=' expr		{ $$ = cons ($1, $3); }
115             	;
116             
117             stmt_list : /* empty */			{ $$ = list (); }
118             	| stmt_list stmt 		{ list_append ($1, $2); }
119             	;
120             
121             stmt	: tRETURN ';'			{ $$ = mk_stmt (sRETURN, NULL, NULL,
122             							NULL, NULL); }
123             	| tRETURN expr ';'		{ $$ = mk_stmt (sRETURN, $2, NULL,
124             							NULL, NULL); }
125             	| tSUB tSYMBOL '(' symbol_list ')' '{' locals stmt_list '}'
126             					{ $$ = mk_stmt (sDEFSUB, $2,
127 rizwank 1.1 							cons (cons ($4, $7),
128             							      $8),
129             							NULL, NULL); }
130             	| '{' stmt_list '}'		{ $$ = mk_stmt (sBLOCK, $2, NULL,
131             							NULL, NULL); }
132             	| tIF '(' expr ')' stmt		{ $$ = mk_stmt (sIF, $3, $5, NULL,
133             							NULL); }
134             	| tIF '(' expr ')' stmt tELSE stmt
135             					{ $$ = mk_stmt (sIF, $3, $5, $7,
136             							NULL); }
137             	| tWHILE '(' expr ')' stmt 	{ $$ = mk_stmt (sWHILE, $3, $5,
138             							NULL, NULL); }
139             	| tFOR '(' cond_expr ';' expr ';' cond_expr ')' stmt
140             					{ $$ = mk_stmt (sFOR, $3, $5, $7,
141             							$9); }
142             	| expr ';'			{ $$ = mk_stmt (sEXPR, $1, NULL,
143             							NULL, NULL); }
144             	;
145             
146             expr	: tSTRING 			{ $$ = mk_expr (eSTRING, $1, NULL,
147             							NULL); }
148 rizwank 1.1 	| tREGEXP			{ $$ = mk_expr (eREGEXP, $1, NULL,
149             							NULL); }
150             	| tINTEGER			{ $$ = mk_expr (eINTEGER, $1, NULL,
151             							NULL); }
152             	| tREAL				{ $$ = mk_expr (eREAL, $1, NULL,
153             							NULL); }
154             	| tSYMBOL			{ $$ = mk_expr (eSYMBOL, $1, NULL,
155             							NULL); }
156             	| '!' expr			{ $$ = mk_expr (eNOT, $2, NULL,
157             							NULL); }
158             	| expr tAND expr		{ $$ = mk_expr (eAND, $1, $3, NULL); }
159             	| expr tOR expr			{ $$ = mk_expr (eOR, $1, $3, NULL); }
160             	| tSYMBOL '(' expr_list ')'	{ $$ = mk_expr (eFCALL, $1, $3,
161             							NULL); }
162             	| tSYMBOL '=' expr		{ $$ = mk_expr (eASSIGN, $1, $3,
163             							NULL); }
164             	| tSYMBOL tADDASSIGN expr	{ $$ = mk_expr (eADDASSIGN, $1, $3,
165             							NULL); }
166             	| tSYMBOL tSUBASSIGN expr	{ $$ = mk_expr (eSUBASSIGN, $1, $3,
167             							NULL); }
168             	| tSYMBOL tMULASSIGN expr	{ $$ = mk_expr (eMULASSIGN, $1, $3,
169 rizwank 1.1 							NULL); }
170             	| tSYMBOL tDIVASSIGN expr	{ $$ = mk_expr (eDIVASSIGN, $1, $3,
171             							NULL); }
172             	| tSYMBOL tPLUSPLUS		{ $$ = mk_expr (ePOSTFIXADD, $1, NULL,
173             							NULL); }
174             	| tSYMBOL tMINUSMINUS		{ $$ = mk_expr (ePOSTFIXSUB, $1, NULL,
175             							NULL); }
176             	| tPLUSPLUS tSYMBOL		{ $$ = mk_expr (ePREFIXADD, $2, NULL,
177             							NULL); }
178             	| tMINUSMINUS tSYMBOL		{ $$ = mk_expr (ePREFIXSUB, $2, NULL,
179             							NULL); }
180             	| expr '[' expr ']' '=' expr	{ $$ = mk_expr (eARRAYASSIGN, $1, $3,
181             							$6); }
182             	| '(' expr ')'			{ $$ = $2; }
183             	| expr '[' expr ']'		{ $$ = mk_expr (eARRAYREF, $1, $3,
184             							NULL); }
185             	| expr '?' expr ':' expr	{ $$ = mk_expr (eQUESTCOLON, $1, $3,
186             							$5); }
187             	| expr '*' expr			{ $$ = mk_expr (eMULT, $1, $3, NULL); }
188             	| expr tDIV expr		{ $$ = mk_expr (eDIV, $1, $3, NULL); }
189             	| expr '+' expr			{ $$ = mk_expr (ePLUS, $1, $3, NULL); }
190 rizwank 1.1 	| expr '-' expr			{ $$ = mk_expr (eMINUS, $1, $3,
191             							NULL); }
192             	| expr '<' expr			{ $$ = mk_expr (eLT, $1, $3, NULL); }
193             	| expr '>' expr			{ $$ = mk_expr (eGT, $1, $3, NULL); }
194             	| expr tEQ expr			{ $$ = mk_expr (eEQ, $1, $3, NULL); }
195             	| expr tNE expr			{ $$ = mk_expr (eNE, $1, $3, NULL); }
196             	| expr tGE expr			{ $$ = mk_expr (eGE, $1, $3, NULL); }
197             	| expr tLE expr			{ $$ = mk_expr (eLE, $1, $3, NULL); }
198             	;
199             
200             cond_expr : /* empty */			{ $$ = NULL; }
201             	| expr				{ $$ = $1; }
202             	;
203             
204             expr_list : /* empty */ 		{ $$ = list (); }
205             	| rest_expr_list 		{ $$ = $1; }
206             	;
207             
208             rest_expr_list: expr 	 		{ $$ = list (); list_append ($$, $1); }
209             	| rest_expr_list ',' expr  	{ list_append ($1, $3); }
210             	;
211 rizwank 1.1 
212             %%
213             
214             void
215             yyerror (msg)
216                  char *msg;
217             {
218               fprintf (stderr, "%s:%d: %s\n", yyin_name, linenum, msg);
219             }