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| chunli@blog:~$ cat eval.y
%define api.pure full
%locations
%param { yyscan_t scanner }
%code top {
#include <stdio.h>
}
%code requires {
typedef void* yyscan_t;
}
%code {
#define YY_EXTRA_TYPE void*
int yylex(YYSTYPE* yylvalp, YYLTYPE* yyllocp, yyscan_t scanner);
void yyerror(YYLTYPE* yyllocp, yyscan_t unused, const char* msg);
char *yyget_text ( yyscan_t scanner );
int yyget_leng ( yyscan_t scanner );
FILE *yyget_in ( yyscan_t scanner );
FILE *yyget_out ( yyscan_t scanner );
int yyget_lineno ( yyscan_t scanner );
int yyget_debug ( yyscan_t scanner );
YY_EXTRA_TYPE yyget_extra ( yyscan_t scanner );
void yyset_debug ( int flag, yyscan_t scanner );
void yyset_in ( FILE * in_str , yyscan_t scanner );
void yyset_out ( FILE * out_str , yyscan_t scanner );
void yyset_lineno ( int line_number , yyscan_t scanner );
void yyset_extra ( YY_EXTRA_TYPE user_defined , yyscan_t scanner );
}
%token NUMBER UNOP
%left '+' '-'
%left '*' '/' '%'
%precedence UNOP
%%
input: %empty
| input expr '\n' { fprintf(yyget_out(scanner), "[%d]: %d\n", @2.first_line, $2); }
| input '\n'
| input error '\n' { yyerrok; }
expr : NUMBER
| '(' expr ')' { printf("Bison File:%s 规约识别()\n", (const char*)yyget_extra(scanner)); $$ = $2; }
| '-' expr %prec UNOP { printf("Bison File:%s 规约识别 -\n", (const char*)yyget_extra(scanner)); $$ = -$2; }
| expr '+' expr { printf("Bison File:%s 规约识别 +\n", (const char*)yyget_extra(scanner)); $$ = $1 + $3; }
| expr '-' expr { printf("Bison File:%s 规约识别 -\n", (const char*)yyget_extra(scanner)); $$ = $1 - $3; }
| expr '*' expr { printf("Bison File:%s 规约识别 *\n", (const char*)yyget_extra(scanner)); $$ = $1 * $3; }
| expr '/' expr { printf("Bison File:%s 规约识别 /\n", (const char*)yyget_extra(scanner)); $$ = $1 / $3; }
| expr '%' expr { printf("Bison File:%s 规约识别%%\n", (const char*)yyget_extra(scanner)); $$ = $1 % $3; }
%%
void yyerror(YYLTYPE* yyllocp, yyscan_t scanner, const char* msg)
{
fprintf(stderr, "Bison File:%s [%d:%d]: %s\n", (const char*)yyget_extra(scanner), yyllocp->first_line, yyllocp->first_column, msg);
}
chunli@blog:~$
|
