option noyywrap bison-bridge bison-locations include stdio include std

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%option noyywrap bison-bridge bison-locations
%{
#include <stdio.h>
#include <stdlib.h>
#define TAG_IDENT 1
#define TAG_OPERATION 2
#define TAG_NUMBER 3
char *tag_names[] =
{
"END_OF_PROGRAM", "IDENT", "OPERATION", "NUMBER"
};
struct Position
{
int line , pos , index ;
};
void print_pos ( struct Position *p )
{
printf("(%d,%d)" ,p->line, p->pos);
}
struct Fragment
{
struct Position starting , following;
};
typedef struct Fragment YYLTYPE;
void print_frag ( struct Fragment *f )
{
print_pos (&(f->starting));
printf ("-");
print_pos(&(f->following));
}
union Token {
char *ident;
long num;
char ch;
};
typedef union Token YYSTYPE;
int continued;
struct Position cur;
#define YY_USER_ACTION \
{ \
int i; \
if (! continued) \
yylloc->starting = cur; \
continued = 0; \
\
for (i = 0; i < yyleng; i++) \
{ \
if (yytext[i] == '\n') \
{ \
cur.line++; \
cur.pos = 1; \
} \
else \
cur.pos++; \
cur.index++; \
} \
\
yylloc->following = cur; \
}
void init_scanner(char *program)
{
continued = 0;
cur.line = 1;
cur.pos =1;
cur.index = 0;
yy_scan_string(program);
}
void err(char *msg)
{
printf("Error ");
print_pos(&cur);
printf(": %s\n",msg);
}
%}
SPACE [\n\t ]+
LETTER [a-zA-Z]
DIGIT [0-9]
OPERATION \(\)|:|:=
IDENT (({LETTER}*)|(\({DIGIT}*\)))
NUMBER (0)|([1-9][0-9]*)
%x COMMENTS LETTER_FIRST DIGIT_FIRST ERROR
%%
{SPACE}
{NUMBER} {
yylval->ident = yytext;
return TAG_NUMBER;
}
{OPERATION} {
yylval->ident = yytext;
return TAG_OPERATION;
}
{IDENT} {
yylval->ident = yytext;
return TAG_IDENT;
}
. err("unexpected character");
%%
#define PROGRAM " () : := 0 456789 034567 (2221) yxtucyivuboi 465vhb"
int main ()
{
int tag;
YYSTYPE value;
YYLTYPE coords;
init_scanner (PROGRAM);
do
{
tag = yylex (&value ,&coords);
if (tag != 0)
{
print_frag(&coords);
printf(" %s %s\n", tag_names[tag], value.ident);
}
}
while ( tag != 0);
return 0;
}