/* Copyright (C) 2008-2013 Free Software Foundation, Inc. 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 3 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, see <http://www.gnu.org/licenses/>. */ %debug %skeleton "lalr1.cc" %defines %define api.token.constructor %define api.value.type variant %define parse.assert %locations %code requires // *.hh { #include <list> #include <string> typedef std::list<std::string> strings_type; } %code // *.cc { #include <algorithm> #include <iostream> #include <iterator> #include <sstream> // Prototype of the yylex function providing subsequent tokens. namespace yy { static parser::symbol_type yylex (); } // Printing a list of strings. // Koening look up will look into std, since that's an std::list. namespace std { std::ostream& operator<< (std::ostream& o, const strings_type& s) { std::copy (s.begin (), s.end (), std::ostream_iterator<strings_type::value_type> (o, "\n")); return o; } } // Conversion to string. template <typename T> inline std::string string_cast (const T& t) { std::ostringstream o; o << t; return o.str (); } } %token <::std::string> TEXT; %token <int> NUMBER; %printer { yyoutput << $$; } <*>; %token END_OF_FILE 0; %type <::std::string> item; %type <::std::list<std::string>> list; %% result: list { std::cout << $1 << std::endl; } ; list: /* nothing */ { /* Generates an empty string list */ } | list item { std::swap ($$, $1); $$.push_back ($2); } ; item: TEXT { std::swap ($$, $1); } | NUMBER { $$ = string_cast ($1); } ; %% namespace yy { // The yylex function providing subsequent tokens: // TEXT "I have three numbers for you." // NUMBER 1 // NUMBER 2 // NUMBER 3 // TEXT "And that's all!" // END_OF_FILE static parser::symbol_type yylex () { static int stage = -1; ++stage; parser::location_type loc(0, stage + 1, stage + 1); switch (stage) { case 0: return parser::make_TEXT ("I have three numbers for you.", loc); case 1: case 2: case 3: return parser::make_NUMBER (stage, loc); case 4: return parser::make_TEXT ("And that's all!", loc); default: return parser::make_END_OF_FILE (loc); } } // Mandatory error function void parser::error (const parser::location_type& loc, const std::string& msg) { std::cerr << loc << ": " << msg << std::endl; } } int main () { yy::parser p; p.set_debug_level (!!getenv ("YYDEBUG")); return p.parse (); } // Local Variables: // mode: C++ // End: