| /*============================================================================= |
| Copyright (c) 2001-2011 Joel de Guzman |
| |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| ==============================================================================*/ |
| #if !defined(BOOST_SPIRIT_LAZY_MARCH_27_2007_1002AM) |
| #define BOOST_SPIRIT_LAZY_MARCH_27_2007_1002AM |
| |
| #if defined(_MSC_VER) |
| #pragma once |
| #endif |
| |
| #include <boost/spirit/home/qi/domain.hpp> |
| #include <boost/spirit/home/qi/skip_over.hpp> |
| #include <boost/spirit/home/qi/meta_compiler.hpp> |
| #include <boost/spirit/home/qi/detail/attributes.hpp> |
| #include <boost/spirit/home/support/unused.hpp> |
| #include <boost/spirit/home/support/info.hpp> |
| #include <boost/spirit/home/support/lazy.hpp> |
| #include <boost/spirit/include/phoenix_core.hpp> |
| #include <boost/fusion/include/at.hpp> |
| #include <boost/utility/result_of.hpp> |
| #include <boost/type_traits/remove_reference.hpp> |
| #include <boost/mpl/not.hpp> |
| |
| namespace boost { namespace spirit |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| // Enablers |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename Eval> |
| struct use_terminal<qi::domain, phoenix::actor<Eval> > // enables phoenix actors |
| : mpl::true_ {}; |
| |
| // forward declaration |
| template <typename Terminal, typename Actor, int Arity> |
| struct lazy_terminal; |
| }} |
| |
| namespace boost { namespace spirit { namespace qi |
| { |
| using spirit::lazy; |
| typedef modify<qi::domain> qi_modify; |
| |
| namespace detail |
| { |
| template <typename Parser, typename Iterator, typename Context |
| , typename Skipper, typename Attribute> |
| bool lazy_parse_impl(Parser const& p |
| , Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper |
| , Attribute& attr, mpl::false_) |
| { |
| return p.parse(first, last, context, skipper, attr); |
| } |
| |
| template <typename Parser, typename Iterator, typename Context |
| , typename Skipper, typename Attribute> |
| bool lazy_parse_impl(Parser const& p |
| , Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper |
| , Attribute& /*attr*/, mpl::true_) |
| { |
| // If DeducedAuto is false (semantic actions is present), the |
| // component's attribute is unused. |
| return p.parse(first, last, context, skipper, unused); |
| } |
| |
| template <typename Parser, typename Iterator, typename Context |
| , typename Skipper, typename Attribute> |
| bool lazy_parse_impl_main(Parser const& p |
| , Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper |
| , Attribute& attr) |
| { |
| // If DeducedAuto is true (no semantic action), we pass the parser's |
| // attribute on to the component. |
| typedef typename traits::has_semantic_action<Parser>::type auto_rule; |
| return lazy_parse_impl(p, first, last, context, skipper, attr, auto_rule()); |
| } |
| } |
| |
| template <typename Function, typename Modifiers> |
| struct lazy_parser : parser<lazy_parser<Function, Modifiers> > |
| { |
| template <typename Context, typename Iterator> |
| struct attribute |
| { |
| typedef typename |
| boost::result_of<qi_modify(tag::lazy_eval, Modifiers)>::type |
| modifier; |
| |
| typedef typename |
| remove_reference< |
| typename boost::result_of<Function(unused_type, Context)>::type |
| >::type |
| expr_type; |
| |
| // If you got an error_invalid_expression error message here, |
| // then the expression (expr_type) is not a valid spirit qi |
| // expression. |
| BOOST_SPIRIT_ASSERT_MATCH(qi::domain, expr_type); |
| |
| typedef typename |
| result_of::compile<qi::domain, expr_type, modifier>::type |
| parser_type; |
| |
| typedef typename |
| traits::attribute_of<parser_type, Context, Iterator>::type |
| type; |
| }; |
| |
| lazy_parser(Function const& function_, Modifiers const& modifiers_) |
| : function(function_), modifiers(modifiers_) {} |
| |
| template <typename Iterator, typename Context |
| , typename Skipper, typename Attribute> |
| bool parse(Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper |
| , Attribute& attr) const |
| { |
| return detail::lazy_parse_impl_main( |
| compile<qi::domain>(function(unused, context) |
| , qi_modify()(tag::lazy_eval(), modifiers)) |
| , first, last, context, skipper, attr); |
| } |
| |
| template <typename Context> |
| info what(Context& context) const |
| { |
| return info("lazy" |
| , compile<qi::domain>(function(unused, context) |
| , qi_modify()(tag::lazy_eval(), modifiers)) |
| .what(context) |
| ); |
| } |
| |
| Function function; |
| Modifiers modifiers; |
| }; |
| |
| |
| template <typename Function, typename Subject, typename Modifiers> |
| struct lazy_directive |
| : unary_parser<lazy_directive<Function, Subject, Modifiers> > |
| { |
| typedef Subject subject_type; |
| |
| template <typename Context, typename Iterator> |
| struct attribute |
| { |
| typedef typename |
| boost::result_of<qi_modify(tag::lazy_eval, Modifiers)>::type |
| modifier; |
| |
| typedef typename |
| remove_reference< |
| typename boost::result_of<Function(unused_type, Context)>::type |
| >::type |
| directive_expr_type; |
| |
| typedef typename |
| proto::result_of::make_expr< |
| proto::tag::subscript |
| , directive_expr_type |
| , Subject |
| >::type |
| expr_type; |
| |
| // If you got an error_invalid_expression error message here, |
| // then the expression (expr_type) is not a valid spirit qi |
| // expression. |
| BOOST_SPIRIT_ASSERT_MATCH(qi::domain, expr_type); |
| |
| typedef typename |
| result_of::compile<qi::domain, expr_type, modifier>::type |
| parser_type; |
| |
| typedef typename |
| traits::attribute_of<parser_type, Context, Iterator>::type |
| type; |
| }; |
| |
| lazy_directive( |
| Function const& function_ |
| , Subject const& subject_ |
| , Modifiers const& modifiers_) |
| : function(function_), subject(subject_), modifiers(modifiers_) {} |
| |
| template <typename Iterator, typename Context |
| , typename Skipper, typename Attribute> |
| bool parse(Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper |
| , Attribute& attr) const |
| { |
| return detail::lazy_parse_impl_main(compile<qi::domain>( |
| proto::make_expr<proto::tag::subscript>( |
| function(unused, context) |
| , subject) |
| , qi_modify()(tag::lazy_eval(), modifiers)) |
| , first, last, context, skipper, attr); |
| } |
| |
| template <typename Context> |
| info what(Context& context) const |
| { |
| return info("lazy-directive" |
| , compile<qi::domain>( |
| proto::make_expr<proto::tag::subscript>( |
| function(unused, context) |
| , subject |
| ), qi_modify()(tag::lazy_eval(), modifiers)) |
| .what(context) |
| ); |
| } |
| |
| Function function; |
| Subject subject; |
| Modifiers modifiers; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // Parser generators: make_xxx function (objects) |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename Eval, typename Modifiers> |
| struct make_primitive<phoenix::actor<Eval>, Modifiers> |
| { |
| typedef lazy_parser<phoenix::actor<Eval>, Modifiers> result_type; |
| result_type operator()(phoenix::actor<Eval> const& f |
| , Modifiers const& modifiers) const |
| { |
| return result_type(f, modifiers); |
| } |
| }; |
| |
| template <typename Terminal, typename Actor, int Arity, typename Modifiers> |
| struct make_primitive<lazy_terminal<Terminal, Actor, Arity>, Modifiers> |
| { |
| typedef lazy_parser<Actor, Modifiers> result_type; |
| result_type operator()( |
| lazy_terminal<Terminal, Actor, Arity> const& lt |
| , Modifiers const& modifiers) const |
| { |
| return result_type(lt.actor, modifiers); |
| } |
| }; |
| |
| template <typename Terminal, typename Actor, int Arity, typename Subject, typename Modifiers> |
| struct make_directive<lazy_terminal<Terminal, Actor, Arity>, Subject, Modifiers> |
| { |
| typedef lazy_directive<Actor, Subject, Modifiers> result_type; |
| result_type operator()( |
| lazy_terminal<Terminal, Actor, Arity> const& lt |
| , Subject const& subject, Modifiers const& modifiers) const |
| { |
| return result_type(lt.actor, subject, modifiers); |
| } |
| }; |
| }}} |
| |
| namespace boost { namespace spirit { namespace traits |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename Actor, typename Modifiers, typename Attribute |
| , typename Context, typename Iterator> |
| struct handles_container< |
| qi::lazy_parser<Actor, Modifiers>, Attribute, Context, Iterator> |
| : handles_container< |
| typename qi::lazy_parser<Actor, Modifiers>::template |
| attribute<Context, Iterator>::parser_type |
| , Attribute, Context, Iterator> |
| {}; |
| |
| template <typename Subject, typename Actor, typename Modifiers |
| , typename Attribute, typename Context, typename Iterator> |
| struct handles_container< |
| qi::lazy_directive<Actor, Subject, Modifiers>, Attribute |
| , Context, Iterator> |
| : handles_container< |
| typename qi::lazy_directive<Actor, Subject, Modifiers>::template |
| attribute<Context, Iterator>::parser_type |
| , Attribute, Context, Iterator> |
| {}; |
| }}} |
| |
| #endif |