X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fparser%2Flexer.cpp;h=cc3be3d91768c1f930b89bd71b12ca8a0672e410;hp=ed1f894fea381bdc9c553d9a2811ff12b1697bcb;hb=44f71c740cc727dc30436e240b9a27021a6d7fdf;hpb=1222eac51cee964961d2aad889dc4ceccb144a36

diff --git a/ginac/parser/lexer.cpp b/ginac/parser/lexer.cpp
index ed1f894f..cc3be3d9 100644
--- a/ginac/parser/lexer.cpp
+++ b/ginac/parser/lexer.cpp
@@ -1,11 +1,35 @@
-#include <string>
+/** @file lexer.cpp
+ *
+ *  Implementation of GiNaC's lexer. */
+
+/*
+ *  GiNaC Copyright (C) 1999-2009 Johannes Gutenberg University Mainz, Germany
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program 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 program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "lexer.h"
+#include "compiler.h"
+
 #include <iostream>
 #include <sstream>
-#include "lexer.hpp"
-#include "compiler.h"
+#include <string>
+#include <cstdio>
+
+namespace GiNaC {
 
-namespace GiNaC
-{
 /// Skip to the end of line
 static int skipline(std::istream* s);
 /// Skip to the next non-whitespace character
@@ -19,12 +43,12 @@ int lexer::gettok()
 	// Skip any whitespace.
 	c = skipspace(input, c, line_num);
 
-	// identifier: [a-zA-Z][a-zA-Z0-9]*
+	// identifier: [a-zA-Z][a-zA-Z0-9_]*
 	if (isalpha(c)) { 
 		str = c;
 		do {
 			c = input->get();
-			if (isalnum(c))
+			if ( isalnum(c) || c=='_' )
 				str += c;
 			else
 				break;
@@ -35,13 +59,23 @@ int lexer::gettok()
 			return token_type::identifier;
 	}
 
-	// Number: [0-9.]+
+	// Number: [0-9]+([.][0-9]*(eE[+-][0-9]+)*)*
 	if (isdigit(c) || c == '.') {
 		str = "";
 		do {
 			str += c;
 			c = input->get();
 		} while (isdigit(c) || c == '.');
+		if (c == 'E' || c == 'e') {
+			str += 'E';
+			c = input->get();
+			if (isdigit(c))
+				str += '+';
+			do {
+				str += c;
+				c = input->get();
+			} while (isdigit(c));
+		}
 		return token_type::number;
 	}
 
@@ -126,7 +160,21 @@ void lexer::switch_input(std::istream* in)
 	input = in;
 	line_num = 0;
 	column = 0;
+	c = ' ';
 }
 
-} // namespace GiNaC
+/// Symbolic name of current token (for error reporting)
+std::string lexer::tok2str(const int tok) const
+{
+	switch (tok) {
+		case lexer::token_type::identifier:
+		case lexer::token_type::number:
+			return std::string("\"") + str + "\"";
+		case lexer::token_type::eof:
+			return std::string("EOF");
+		default:
+			return std::string("\"") + char(tok) + "\"";
+	}
+}
 
+} // namespace GiNaC