diff -r 08b64ae5a564 -r 6e1027a05d73 lemon/bits/item_writer.h
--- a/lemon/bits/item_writer.h	Thu Apr 19 15:12:59 2007 +0000
+++ b/lemon/bits/item_writer.h	Thu Apr 19 15:14:34 2007 +0000
@@ -31,6 +31,9 @@
 #include <deque>
 #include <list>
 #include <set>
+#include <map>
+
+#include <lemon/error.h>
 
 namespace lemon {
   
@@ -146,13 +149,14 @@
     ///
     /// Constructor for the writer. If the given parameter is true
     /// the writer creates escape sequences from special characters.
-    QuotedStringWriter(bool _escaped = true) : escaped(_escaped) {}
+    QuotedStringWriter(bool _escaped = true, char _quote = '\"') 
+      : escaped(_escaped), quote(_quote) {}
 
     /// \brief Writes a quoted string to the given stream.
     ///
     /// Writes a quoted string to the given stream.
     void write(std::ostream& os, const std::string& value) const {
-      os << "\"";
+      os << quote;
       if (escaped) {
 	std::ostringstream ls;
 	for (int i = 0; i < int(value.size()); ++i) {
@@ -162,7 +166,7 @@
       } else {
 	os << value;
       }
-      os << "\"";
+      os << quote;
     }
 
   private:
@@ -213,6 +217,7 @@
     }
   private:
     bool escaped;
+    char quote;
   };
 
   /// \ingroup item_io