scanner.l
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/*****************************************************************************/
/* */
/* Projecto de Compiladores ---------------------------------- VSPL */
/* */
/* Lex Scanner Specification. */
/* */
/* Salvador Pinto Abreu */
/* */
/*****************************************************************************/
/*****************************************************************************/
/* */
/* Prelude. */
/* */
/*****************************************************************************/
%{
#include <ctype.h>
#include <strings.h>
#include <math.h>
#include "types.h"
#include "y.tab.h"
static char buffer[512];
#define ret(v) return(v)
#define value(c,t,v) yylval.t = v; ret (c)
#define T yytext
#define D(X,S) (((yytext[X])-'0')<<S)
%}
letter [a-zA-Z]
digit [0-9]
id {letter}({letter}|{digit}|_)*
exp ([eE][-+]?{digit}+)
%start ERROR
%p 5000
%a 3000
%%
<ERROR>[^ \t\n]* { setup_lc();
yyerror ("illegal character(s) in input");
BEGIN 0; }
"#".* { setup_lc(); }
[ \t]+ { setup_lc(); }
\n { setup_lc(); }
{digit}*\.{digit}+{exp}? { value (REAL_LIT, lit.rval, atof(T)); }
{digit}+\.{digit}*{exp}? { value (REAL_LIT, lit.rval, atof(T)); }
{digit}+{exp} { value (REAL_LIT, lit.rval, atof(T)); }
{digit}+ { value (INT_LIT, lit.ival, atoi(T)); }
\" { register char *tx = buffer;
register int c;
while ((c = input()) && (c != '"')) {
if (c == '\\') {
c = input();
if (isdigit(c)) {
register int x = c-'0';
while (isdigit(c=input())) {
x <<= 3;
x += c-'0';
}
unput(c);
c = x;
}
else switch (c) {
case 'n': c = '\n'; break;
case 'r': c = '\r'; break;
case 't': c = '\t'; break;
case 'b': c = '\b'; break;
case 'f': c = '\f'; break;
default: break;
}
}
if ((*tx++ = c) == '\'')
*tx++ = c;
}
*tx = 0;
value (STRING_LIT, lit.sval, buffer); }
true { value (BOOL_LIT, lit.bval, true); }
false { value (BOOL_LIT, lit.bval, false); }
int { ret (INT); }
real { ret (REAL); }
bool { ret (BOOL); }
string { ret (STRING); }
map { ret (MAP); }
class { ret (CLASS); }
return { ret (RETURN); }
"^" { ret (RETURN); }
recurse { ret (RECURSE); }
"@" { ret (RECURSE); }
break { ret (BREAK); }
skip { ret (SKIP); }
retry { ret (RETRY); }
else { ret (ELSE); }
"_" { ret (ELSE); }
"*"/[ \t]*"->" { ret (ELSE); }
cond { ret (COND); }
"?" { ret (COND); }
while { ret (WHILE); }
"*"/[ \t]*"[" { ret (WHILE); }
and { ret (AND); }
or { ret (OR); }
not { ret (NOT); }
{id} { value (ID, id, lookup(T)); }
"<" { ret (LT); }
"<=" { ret (LE); }
"=" { ret (EQ); }
"~=" { ret (NE); }
"<>" { ret (NE); }
">=" { ret (GE); }
">" { ret (GT); }
"+" { ret ('+'); }
"-" { ret ('-'); }
"*" { ret ('*'); }
"/" { ret ('/'); }
"%" { ret ('%'); }
";" { ret (';'); }
"," { ret (','); }
"." { ret ('.'); }
":" { ret (':'); }
"|" { ret ('|'); }
"->" { ret (RETURNS); }
":=" { ret (ASSIGN); }
"==" { ret (IDENTICAL); }
"(" { ret ('('); }
")" { ret (')'); }
"[" { ret ('['); }
"]" { ret (']'); }
"{" { ret ('{'); }
"}" { ret ('}'); }
"?" { ret ('?'); }
. { BEGIN ERROR; }
%%
error (msg)
char *msg;
{
fprintf (stderr, msg);
}