+
+class parse_error: public std::runtime_error
+{
+public:
+ parse_error(const std::string &);
+ virtual ~parse_error() throw() { }
+};
+
+
+class syntax_error: public std::runtime_error
+{
+public:
+ syntax_error(const std::string &t);
+ virtual ~syntax_error() throw() { }
+};
+
+
+class bad_definition: public std::runtime_error
+{
+public:
+ bad_definition(const std::string &w);
+ virtual ~bad_definition() throw() { }
+};
+
+
+class nesting_error: public std::logic_error