/* 
 * A scanner for a toy language lex.l 
 */

%{ // Copied verbatim

#include <string.h>
#include <stdlib.h>
#include "y.tab.h"  // tokens are defined 
int line_count = 1; yylType yylval;     
 
%}

%option noyywrap
%x CMNT INSTR            

DELIM      ([ \t])
WHITESPACES ({DELIM}+)
P_DIG   ([1-9])
DIG    (0|{P_DIG})
NN_INT    (0|{P_DIG}{DIG}*)
LOWER      ([a-z])
LETTER     ({LOWER}|[:upper:])
IDENTIFIER (({LETTER}({LETTER}|{DIG})*)|(_+({LETTER}|{DIG})+))

%%

"/*"         {BEGIN CMNT;}
<CMNT>.      {;}
<CMNT>\n     {++line_count;}
<CMNT>"*/"   {BEGIN INITIAL;}
\n           {
              ++line_count; 
              return (int)'\n';
             }
"\"".*"\""   {
 yylval.string=(char *)malloc((yyleng+1)*(sizeof(char)));
 strncpy(yylval.string, yytext+1, yyleng-2);
 yylval.string[yyleng-2]='\0';
 return STRNG; 
             }
{WHITESPACES} { ; }
if           {return IF;}
else         {return ELSE; }
while        { return WHILE; }
for          { return FOR; }
int          { return INT; }
\(           { return (int)'('; }
\)           { return (int)')'; }
\{           { return (int)'{'; }
\}           { return (int)'}'; }
;            { return (int)';'; }
,            { return (int)','; }
=            { return (int)'='; }
"<"          { return (int)'<'; }
"<="         { return LEQ; }
"&"          { return (int)'&'; }
"+"          { 
               yylval.integer = (int)'+'; 
               return BIN_OP;
             }
"-"          { 
               yylval.integer = (int)'-'; 
               return BIN_OP;
             }
"*"          { 
               yylval.integer = (int)'*'; 
               return BIN_OP;
             }
"/"          { 
               yylval.integer = (int)'/'; 
               return BIN_OP;
              }
{IDENTIFIER} {
  yylval.string=(char *)malloc((yyleng+1)*(sizeof(char)));
  strncpy(yylval.string, yytext, yyleng);
  yylval.string[yyleng]='\0';
  return ID; 
             } 
{NN_INT}    { 
               yylval.integer = atoi(yytext); 
               return NUM; 
             }
.            { printf("Invalid symbol %s at line %d\n", 
                                 yytext, line_count); }
%%
/* The function yywrap()  */
//int yywrap(){return 1;}