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Diffstat (limited to 'src/third_party/boost-1.60.0/boost/spirit/home/classic/core/non_terminal/rule.hpp')
-rw-r--r-- | src/third_party/boost-1.60.0/boost/spirit/home/classic/core/non_terminal/rule.hpp | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/src/third_party/boost-1.60.0/boost/spirit/home/classic/core/non_terminal/rule.hpp b/src/third_party/boost-1.60.0/boost/spirit/home/classic/core/non_terminal/rule.hpp new file mode 100644 index 00000000000..1d4336bcc94 --- /dev/null +++ b/src/third_party/boost-1.60.0/boost/spirit/home/classic/core/non_terminal/rule.hpp @@ -0,0 +1,175 @@ +/*============================================================================= + Copyright (c) 1998-2003 Joel de Guzman + http://spirit.sourceforge.net/ + + 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_RULE_HPP) +#define BOOST_SPIRIT_RULE_HPP + +#include <boost/static_assert.hpp> + +/////////////////////////////////////////////////////////////////////////////// +// +// Spirit predefined maximum number of simultaneously usable different +// scanner types. +// +// This limit defines the maximum number of possible different scanner +// types for which a specific rule<> may be used. If this isn't defined, a +// rule<> may be used with one scanner type only (multiple scanner support +// is disabled). +// +/////////////////////////////////////////////////////////////////////////////// +#if !defined(BOOST_SPIRIT_RULE_SCANNERTYPE_LIMIT) +# define BOOST_SPIRIT_RULE_SCANNERTYPE_LIMIT 1 +#endif + +// Ensure a meaningful maximum number of simultaneously usable scanner types +BOOST_STATIC_ASSERT(BOOST_SPIRIT_RULE_SCANNERTYPE_LIMIT > 0); + +#include <boost/scoped_ptr.hpp> +#include <boost/spirit/home/classic/namespace.hpp> +#include <boost/spirit/home/classic/core/non_terminal/impl/rule.ipp> + +#if BOOST_SPIRIT_RULE_SCANNERTYPE_LIMIT > 1 +# include <boost/preprocessor/enum_params.hpp> +#endif + +/////////////////////////////////////////////////////////////////////////////// +namespace boost { namespace spirit { + +BOOST_SPIRIT_CLASSIC_NAMESPACE_BEGIN + +#if BOOST_SPIRIT_RULE_SCANNERTYPE_LIMIT > 1 + + /////////////////////////////////////////////////////////////////////////// + // + // scanner_list (a fake scanner) + // + // Typically, rules are tied to a specific scanner type and + // a particular rule cannot be used with anything else. Sometimes + // there's a need for rules that can accept more than one scanner + // type. The scanner_list<S0, ...SN> can be used as a template + // parameter to the rule class to specify up to the number of + // scanner types defined by the BOOST_SPIRIT_RULE_SCANNERTYPE_LIMIT + // constant. Example: + // + // rule<scanner_list<ScannerT0, ScannerT1> > r; + // + // *** This feature is available only to compilers that support + // partial template specialization. *** + // + /////////////////////////////////////////////////////////////////////////// + template < + BOOST_PP_ENUM_PARAMS( + BOOST_SPIRIT_RULE_SCANNERTYPE_LIMIT, + typename ScannerT + ) + > + struct scanner_list : scanner_base {}; + +#endif + + /////////////////////////////////////////////////////////////////////////// + // + // rule class + // + // The rule is a polymorphic parser that acts as a named place- + // holder capturing the behavior of an EBNF expression assigned to + // it. + // + // The rule is a template class parameterized by: + // + // 1) scanner (scanner_t, see scanner.hpp), + // 2) the rule's context (context_t, see parser_context.hpp) + // 3) an arbitrary tag (tag_t, see parser_id.hpp) that allows + // a rule to be tagged for identification. + // + // These template parameters may be specified in any order. The + // scanner will default to scanner<> when it is not specified. + // The context will default to parser_context when not specified. + // The tag will default to parser_address_tag when not specified. + // + // The definition of the rule (its right hand side, RHS) held by + // the rule through a scoped_ptr. When a rule is seen in the RHS + // of an assignment or copy construction EBNF expression, the rule + // is held by the LHS rule by reference. + // + /////////////////////////////////////////////////////////////////////////// + template < + typename T0 = nil_t + , typename T1 = nil_t + , typename T2 = nil_t + > + class rule + : public impl::rule_base< + rule<T0, T1, T2> + , rule<T0, T1, T2> const& + , T0, T1, T2> + { + public: + + typedef rule<T0, T1, T2> self_t; + typedef impl::rule_base< + self_t + , self_t const& + , T0, T1, T2> + base_t; + + typedef typename base_t::scanner_t scanner_t; + typedef typename base_t::attr_t attr_t; + typedef impl::abstract_parser<scanner_t, attr_t> abstract_parser_t; + + rule() : ptr() {} + ~rule() {} + + rule(rule const& r) + : ptr(new impl::concrete_parser<rule, scanner_t, attr_t>(r)) {} + + template <typename ParserT> + rule(ParserT const& p) + : ptr(new impl::concrete_parser<ParserT, scanner_t, attr_t>(p)) {} + + template <typename ParserT> + rule& operator=(ParserT const& p) + { + ptr.reset(new impl::concrete_parser<ParserT, scanner_t, attr_t>(p)); + return *this; + } + + rule& operator=(rule const& r) + { + ptr.reset(new impl::concrete_parser<rule, scanner_t, attr_t>(r)); + return *this; + } + + rule<T0, T1, T2> + copy() const + { + return rule<T0, T1, T2>(ptr.get() ? ptr->clone() : 0); + } + + private: + friend class impl::rule_base_access; + + abstract_parser_t* + get() const + { + return ptr.get(); + } + + rule(abstract_parser_t* ptr_) + : ptr(ptr_) {} + + rule(abstract_parser_t const* ptr_) + : ptr(ptr_) {} + + scoped_ptr<abstract_parser_t> ptr; + }; + +BOOST_SPIRIT_CLASSIC_NAMESPACE_END + +}} // namespace BOOST_SPIRIT_CLASSIC_NS + +#endif |