#ifndef _ERROR_H #define _ERROR_H #include #include #include #include #include #include "debug.h" namespace ledger { class error_context { public: string desc; error_context(const string& _desc) throw() : desc(_desc) {} virtual ~error_context() throw() {} virtual void describe(std::ostream& out) const throw() { if (! desc.empty()) out << desc << std::endl; } }; class file_context : public error_context { protected: string file; unsigned long line; public: file_context(const string& _file, unsigned long _line, const string& _desc = "") throw() : error_context(_desc), file(_file), line(_line) {} virtual ~file_context() throw() {} virtual void describe(std::ostream& out) const throw() { if (! desc.empty()) out << desc << " "; out << "\"" << file << "\", line " << line << ": "; } }; class line_context : public error_context { public: string line; long pos; line_context(const string& _line, long _pos, const string& _desc = "") throw() : error_context(_desc), line(_line), pos(_pos) {} virtual ~line_context() throw() {} virtual void describe(std::ostream& out) const throw() { if (! desc.empty()) out << desc << std::endl; out << " " << line << std::endl << " "; long idx = pos < 0 ? line.length() - 1 : pos; for (int i = 0; i < idx; i++) out << " "; out << "^" << std::endl; } }; ////////////////////////////////////////////////////////////////////// class str_exception : public std::exception { protected: string reason; public: std::list context; str_exception(const string& _reason, error_context * ctxt = NULL) throw() : reason(_reason) { if (ctxt) context.push_back(ctxt); } virtual ~str_exception() throw() { for (std::list::iterator i = context.begin(); i != context.end(); i++) delete *i; } virtual void reveal_context(std::ostream& out, const string& kind) const throw() { for (std::list::const_reverse_iterator i = context.rbegin(); i != context.rend(); i++) { std::list::const_reverse_iterator x = i; if (++x == context.rend()) out << kind << ": "; (*i)->describe(out); } } virtual const char* what() const throw() { return reason.c_str(); } }; class error : public str_exception { public: error(const string& _reason, error_context * _ctxt = NULL) throw() : str_exception(_reason, _ctxt) {} virtual ~error() throw() {} }; class fatal : public str_exception { public: fatal(const string& _reason, error_context * _ctxt = NULL) throw() : str_exception(_reason, _ctxt) {} virtual ~fatal() throw() {} }; class fatal_assert : public fatal { public: fatal_assert(const string& _reason, error_context * _ctxt = NULL) throw() : fatal(string("assertion failed '") + _reason + "'", _ctxt) {} virtual ~fatal_assert() throw() {} }; inline void unexpected(char c, char wanted) { if ((unsigned char) c == 0xff) { if (wanted) throw new error(string("Missing '") + wanted + "'"); else throw new error("Unexpected end of input"); } else { if (wanted) throw new error(string("Invalid char '") + c + "' (wanted '" + wanted + "')"); else throw new error(string("Invalid char '") + c + "'"); } } } // namespace ledger #endif // _ERROR_H