double.gsp

This is the verbatim text of the file "double.gsp" part of the LLOOP package. The copyright remains with Michel MEHL. All rights reserved.

/**
 * Reads a "double" C type (including overflow check). 
 */

symbol FloatToken extends class universal::Float()
  include "universal__Numeric.h";

token DoubleToken extends class universal::Double()
  include <stdio.h>, <ctype.h>, "universal__Numeric.h"
  alias "double"
  parse
  {{
    char c = 0;        		
    short iSign = 1;
    short iSignExp = 1;
    universal::String s;
    double dVal = 0.0;
    double dExp = 0.0; 

    is.get(c);
    if (c == '-') 
      {
	iSign = -1;
	is.get(c);
      }
    else if (c == '+') 
      {
	iSign = 1;
	is.get(c);
      }
  
    if (is.fail() || (!isdigit(c) && c != '.' && tolower(c) != 'e' ) )
      {
	abort("");
      }

    // Get integer part

    for (dVal = 0.0; isdigit(c) && !is.fail(); is.get(c))
      dVal = 10.0 * dVal + (c - '0');

    if (c == '.')
      is.get(c);

  // Get decimal part

    for (dExp = 10.0; isdigit(c) && !is.fail(); is.get(c)) {
      dVal = dVal + (c - '0') / dExp;
      dExp *= 10.0;
    }

    // Get exponent
    dExp = 1.0;
    if ( (tolower(c) == 'e') && !is.fail())
      {
	is.get(c);
	if (c == '-') 
	  {
	    iSignExp = -1;
	    is.get(c);
	  }
	else if (c == '+') 
	  {
	    iSignExp = 1;
	    is.get(c);
	  }
      
	if (is.fail() || !isdigit(c))
	  {
	    abort("");
	  }
      
	for (dExp = 0.0; isdigit(c) && !is.fail(); is.get(c)) 
	  dExp = 10.0 * dExp + (c - '0');
      }

    if (!is.fail())
      {
	is.seekg(-1, ios::cur); // Set pos. to the immediate following char 
	double dRes = iSign * dVal / dExp;
	Double::operator=(dRes);
      }
  }}
  expand
  {{
    os << toString();
  }}

FloatToken ::= DoubleToken
{{
  Float::operator=((float)$1); 
}}

This file is part of the LLOOP Reversible Object-Oriented Parser Generator. Copyright (c) 2005-2006 Michel MEHL, France. All rights reserved. LLOOP is distributed by the company ERSA SaRL.