%{
/* 
 * exp3.l is the flex specification for 
 * exp3.y. The exp3.tab.h (y.tab.h) will be created
 * bison (yacc) compiler. Compile as
 * $ flex exp3.l
 * output: lex.yy.c
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "calc.h"
#include "exp3.tab.h"  /* Created by bison */
%}

%option noyywrap

DELIM      ([ \t])
WHITESPACES ({DELIM}+)
NATNUM    ([0-9]+) 
FLOAT      (([0-9]*(\.)?[0-9]+)|([0-9]+(\.)?[0-9]*))
NAME	  ([a-zA-Z])+

%%
{WHITESPACES} { ; }
{FLOAT}       { yylval.val = atof(yytext) ; return NUM ; }
{NAME}        {
                char *symbuf ;
                symrec* symTabP ;
                symbuf = (char *)malloc(LENGTH);
                strncpy(symbuf, yytext, yyleng);
                symbuf[yyleng]='\0';
                symTabP = getsym(symbuf);
                if(symTabP == NULL) symTabP = putsym(symbuf, VAR);
                yylval.symTabPtr = symTabP;
                return symTabP -> type;  // VAR or FUN1 or FUN2
              }
"+"           { return (int)'+' ; }
"-"           { return (int)'-' ; }
"/"           { return (int)'/' ; }
"*"           { return (int)'*' ;}
"\n"	      { return (int)'\n';}
"("	      { return (int)'(';}
")"	      { return (int)')';}
","	      { return (int)',';}
"="	      { return (int)'=';}
                
%%



symrec *getsym (char *sym_name)
{
  symrec *ptr;
  for (ptr = sym_table; ptr != (symrec *) 0;
       ptr = (symrec *)ptr->next)
    if (strcmp (ptr->name,sym_name) == 0)
      return ptr;
  return 0;
}