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f44479bcd3
It is better to manage warnings on our side to know what warnings we need to fix or suppress, and the only thing that header does is disabling deprecation warnings on MSVC and ICC which we would prefer to not show to users.
108 lines
3.4 KiB
C++
108 lines
3.4 KiB
C++
// Copyright (c) 2001-2011 Hartmut Kaiser
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// #define BOOST_SPIRIT_LEXERTL_DEBUG 1
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#include <boost/spirit/include/lex_lexertl.hpp>
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#include <boost/spirit/include/qi.hpp>
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#include <boost/spirit/include/phoenix.hpp>
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namespace lex = boost::spirit::lex;
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namespace qi = boost::spirit::qi;
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namespace phoenix = boost::phoenix;
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///////////////////////////////////////////////////////////////////////////////
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template <typename Lexer>
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struct language_tokens : lex::lexer<Lexer>
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{
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language_tokens()
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{
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tok_float = "float";
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tok_int = "int";
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floatlit = "[0-9]+\\.[0-9]*";
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intlit = "[0-9]+";
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ws = "[ \t\n]+";
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identifier = "[a-zA-Z_][a-zA-Z_0-9]*";
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this->self = ws [lex::_pass = lex::pass_flags::pass_ignore];
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this->self += tok_float | tok_int | floatlit | intlit | identifier;
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this->self += lex::char_('=');
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}
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lex::token_def<> tok_float, tok_int;
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lex::token_def<> ws;
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lex::token_def<double> floatlit;
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lex::token_def<int> intlit;
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lex::token_def<> identifier;
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};
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///////////////////////////////////////////////////////////////////////////////
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template <typename Iterator>
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struct language_grammar : qi::grammar<Iterator>
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{
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template <typename Lexer>
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language_grammar(language_tokens<Lexer> const& tok)
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: language_grammar::base_type(declarations)
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{
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declarations = +number;
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number =
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tok.tok_float >> tok.identifier >> '=' >> tok.floatlit
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| tok.tok_int >> tok.identifier >> '=' >> tok.intlit
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;
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declarations.name("declarations");
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number.name("number");
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debug(declarations);
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debug(number);
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}
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qi::rule<Iterator> declarations;
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qi::rule<Iterator> number;
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};
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///////////////////////////////////////////////////////////////////////////////
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int main()
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{
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// iterator type used to expose the underlying input stream
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typedef std::string::iterator base_iterator_type;
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// lexer type
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typedef lex::lexertl::actor_lexer<
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lex::lexertl::token<
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base_iterator_type, boost::mpl::vector2<double, int>
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> > lexer_type;
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// iterator type exposed by the lexer
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typedef language_tokens<lexer_type>::iterator_type iterator_type;
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// now we use the types defined above to create the lexer and grammar
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// object instances needed to invoke the parsing process
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language_tokens<lexer_type> tokenizer; // Our lexer
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language_grammar<iterator_type> g (tokenizer); // Our parser
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// Parsing is done based on the token stream, not the character
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// stream read from the input.
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std::string str ("float f = 3.4\nint i = 6\n");
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base_iterator_type first = str.begin();
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bool r = lex::tokenize_and_parse(first, str.end(), tokenizer, g);
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if (r) {
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std::cout << "-------------------------\n";
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std::cout << "Parsing succeeded\n";
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std::cout << "-------------------------\n";
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}
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else {
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std::string rest(first, str.end());
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std::cout << "-------------------------\n";
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std::cout << "Parsing failed\n";
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std::cout << "stopped at: \"" << rest << "\"\n";
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std::cout << "-------------------------\n";
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}
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std::cout << "Bye... :-) \n\n";
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return 0;
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}
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