%{
#define YYSTYPE double

#include "parse.h"
int number(void);		/* see below - converts string to double */
extern int fileno(FILE *);	/* to avoid gcc warning */
%}

%option always-interactive

D	[0-9]
E	[Ee][+\-]?{D}+

%%
[ \t\r\v\f]		{ /* ignore whitespace */ }

[*+()\n]		{

  return yytext[0]; /* operators and newline */
}

{D}+({E})?		{

  return number();
}

{D}*"."{D}+({E})?	{ return number(); }
{D}+"."{D}*({E})?	{ return number(); }
.			{ return yytext[0]; /* bad token */ }

%%

void (*jj_junk)(int,char *) = yyunput; /* avoids gcc warnings */
int (*jj2_junk)(void) = input;

void yyerror( const char *msg) /* called for parser syntax error */
{
  printf( "error: %s, yytext: %s\n", msg, yytext);
}

int yywrap( void) /* called at EOF */
{
  return 1;
}

int number( void)
{
  /* Consider using strtod(), can check for overflow. */

  if( sscanf( yytext, "%lf", &yylval ) != 1 )
    return 0;
  else
    return NUMBER;
}