DocScript SVN

/*
 * A simple expression to LaTeX translator: the scanner

 * Copyright (C) 2009
 * Andreas Harnack (ah8 at freenet dot de)

 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License along
 * with this library; see the file COPYING.  If not, write to the Free
 * Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
 * USA.

 * As a special exception, you may use this file as part of a free software
 * library without restriction.  Specifically, if other files instantiate
 * templates or use macros or inline functions from this file, or you compile
 * this file and link it with other files to produce an executable, this
 * file does not by itself cause the resulting executable to be covered by
 * the GNU General Public License.  This exception does not however
 * invalidate any other reasons why the executable file might be covered by
 * the GNU General Public License.
 */

#include "scanner.h"
#include <cctype>

Input& Input::next() {
	while ( isspace(*ch) )
		++ch;
	if ( isdigit(*ch) ) {
		num = *ch++ - '0';
		while ( isdigit(*ch) )
			num = num * 10 + (*ch++ - '0');
		current = Number;
	}
	else switch ( *ch ) {
		case '+':   current = *ch++; break;
		case '-':   current = *ch++; break;
		case '*':   current = *ch++; break;
		case '/':   current = *ch++; break;
		case '(':   current = *ch++; break;
		case ')':   current = *ch++; break;
		case '\0':  current = *ch; break;
		default:
			throw "invalid character";
	}
	return *this;
}