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Diffstat (limited to '3rdParty/Boost/src/boost/parameter/aux_/arg_list.hpp')
| -rw-r--r-- | 3rdParty/Boost/src/boost/parameter/aux_/arg_list.hpp | 459 |
1 files changed, 459 insertions, 0 deletions
diff --git a/3rdParty/Boost/src/boost/parameter/aux_/arg_list.hpp b/3rdParty/Boost/src/boost/parameter/aux_/arg_list.hpp new file mode 100644 index 0000000..ed3929d --- /dev/null +++ b/3rdParty/Boost/src/boost/parameter/aux_/arg_list.hpp @@ -0,0 +1,459 @@ +// Copyright Daniel Wallin, David Abrahams 2005. Use, modification and +// distribution is subject to 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) + +#ifndef ARG_LIST_050329_HPP +#define ARG_LIST_050329_HPP + +#include <boost/parameter/aux_/void.hpp> +#include <boost/parameter/aux_/result_of0.hpp> +#include <boost/parameter/aux_/default.hpp> +#include <boost/parameter/aux_/parameter_requirements.hpp> +#include <boost/parameter/aux_/yesno.hpp> +#include <boost/parameter/aux_/is_maybe.hpp> +#include <boost/parameter/config.hpp> + +#include <boost/mpl/apply.hpp> +#include <boost/mpl/assert.hpp> +#include <boost/mpl/begin.hpp> +#include <boost/mpl/end.hpp> +#include <boost/mpl/iterator_tags.hpp> + +#include <boost/type_traits/add_reference.hpp> +#include <boost/type_traits/is_same.hpp> +#include <boost/preprocessor/repetition/enum_params.hpp> +#include <boost/preprocessor/repetition/enum_binary_params.hpp> +#include <boost/preprocessor/facilities/intercept.hpp> + +namespace boost { namespace parameter { + +// Forward declaration for aux::arg_list, below. +template<class T> struct keyword; + +namespace aux { + +// Tag type passed to MPL lambda. +struct lambda_tag; + +// +// Structures used to build the tuple of actual arguments. The +// tuple is a nested cons-style list of arg_list specializations +// terminated by an empty_arg_list. +// +// Each specialization of arg_list is derived from its successor in +// the list type. This feature is used along with using +// declarations to build member function overload sets that can +// match against keywords. +// + +// MPL sequence support +struct arg_list_tag; + +// Terminates arg_list<> and represents an empty list. Since this +// is just the terminating case you might want to look at arg_list +// first, to get a feel for what's really happening here. + +struct empty_arg_list +{ + empty_arg_list() {} + + // Constructor taking BOOST_PARAMETER_MAX_ARITY empty_arg_list + // arguments; this makes initialization + empty_arg_list( + BOOST_PP_ENUM_PARAMS( + BOOST_PARAMETER_MAX_ARITY, void_ BOOST_PP_INTERCEPT + )) + {} + + // A metafunction class that, given a keyword and a default + // type, returns the appropriate result type for a keyword + // lookup given that default + struct binding + { + template<class KW, class Default, class Reference> + struct apply + { + typedef Default type; + }; + }; + +#if !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) + // Terminator for has_key, indicating that the keyword is unique + template <class KW> + static no_tag has_key(KW*); +#endif + +#if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \ + || (BOOST_WORKAROUND(__GNUC__, < 3)) \ + || BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564)) + + // The overload set technique doesn't work with these older + // compilers, so they need some explicit handholding. + + // A metafunction class that, given a keyword, returns the type + // of the base sublist whose get() function can produce the + // value for that key + struct key_owner + { + template<class KW> + struct apply + { + typedef empty_arg_list type; + }; + }; + + template <class K, class T> + T& get(default_<K,T> x) const + { + return x.value; + } + + template <class K, class F> + typename result_of0<F>::type + get(lazy_default<K,F> x) const + { + return x.compute_default(); + } +#endif + + // If this function is called, it means there is no argument + // in the list that matches the supplied keyword. Just return + // the default value. + template <class K, class Default> + Default& operator[](default_<K, Default> x) const + { + return x.value; + } + + // If this function is called, it means there is no argument + // in the list that matches the supplied keyword. Just evaluate + // and return the default value. + template <class K, class F> + typename result_of0<F>::type + operator[]( + BOOST_PARAMETER_lazy_default_fallback<K,F> x) const + { + return x.compute_default(); + } + + // No argument corresponding to ParameterRequirements::key_type + // was found if we match this overload, so unless that parameter + // has a default, we indicate that the actual arguments don't + // match the function's requirements. + template <class ParameterRequirements, class ArgPack> + static typename ParameterRequirements::has_default + satisfies(ParameterRequirements*, ArgPack*); + + // MPL sequence support + typedef empty_arg_list type; // convenience + typedef arg_list_tag tag; // For dispatching to sequence intrinsics +}; + +#if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) +template<class KW> +no_tag operator*(empty_arg_list, KW*); +#endif + +// Forward declaration for arg_list::operator, +template <class KW, class T> +struct tagged_argument; + +template <class T> +struct get_reference +{ + typedef typename T::reference type; +}; + +// A tuple of tagged arguments, terminated with empty_arg_list. +// Every TaggedArg is an instance of tagged_argument<>. +template <class TaggedArg, class Next = empty_arg_list> +struct arg_list : Next +{ + typedef arg_list<TaggedArg,Next> self; + typedef typename TaggedArg::key_type key_type; + + typedef typename is_maybe<typename TaggedArg::value_type>::type holds_maybe; + + typedef typename mpl::eval_if< + holds_maybe + , get_reference<typename TaggedArg::value_type> + , get_reference<TaggedArg> + >::type reference; + + typedef typename mpl::if_< + holds_maybe + , reference + , typename TaggedArg::value_type + >::type value_type; + + TaggedArg arg; // Stores the argument + + // Store the arguments in successive nodes of this list + template< // class A0, class A1, ... + BOOST_PP_ENUM_PARAMS(BOOST_PARAMETER_MAX_ARITY, class A) + > + arg_list( // A0& a0, A1& a1, ... + BOOST_PP_ENUM_BINARY_PARAMS(BOOST_PARAMETER_MAX_ARITY, A, & a) + ) + : Next( // a1, a2, ... + BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PARAMETER_MAX_ARITY, a) + , void_reference() + ) + , arg(a0) + {} + + // Create a new list by prepending arg to a copy of tail. Used + // when incrementally building this structure with the comma + // operator. + arg_list(TaggedArg head, Next const& tail) + : Next(tail) + , arg(head) + {} + + // A metafunction class that, given a keyword and a default + // type, returns the appropriate result type for a keyword + // lookup given that default + struct binding + { + template <class KW, class Default, class Reference> + struct apply + { + typedef typename mpl::eval_if< + boost::is_same<KW, key_type> + , mpl::if_<Reference, reference, value_type> + , mpl::apply_wrap3<typename Next::binding, KW, Default, Reference> + >::type type; + }; + }; + +#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564)) && !BOOST_WORKAROUND(__GNUC__, == 2) +# if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) + friend yes_tag operator*(arg_list, key_type*); +# define BOOST_PARAMETER_CALL_HAS_KEY(next, key) (*(next*)0 * (key*)0) +# else + // Overload for key_type, so the assert below will fire if the + // same keyword is used again + static yes_tag has_key(key_type*); + using Next::has_key; + +# define BOOST_PARAMETER_CALL_HAS_KEY(next, key) next::has_key((key*)0) +# endif + + BOOST_MPL_ASSERT_MSG( + sizeof(BOOST_PARAMETER_CALL_HAS_KEY(Next,key_type)) == sizeof(no_tag) + , duplicate_keyword, (key_type) + ); + +# undef BOOST_PARAMETER_CALL_HAS_KEY +#endif + // + // Begin implementation of indexing operators for looking up + // specific arguments by name + // + + // Helpers that handle the case when TaggedArg is + // empty<T>. + template <class D> + reference get_default(D const&, mpl::false_) const + { + return arg.value; + } + + template <class D> + reference get_default(D const& d, mpl::true_) const + { + return arg.value ? arg.value.get() : arg.value.construct(d.value); + } + +#if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \ + || BOOST_WORKAROUND(__GNUC__, < 3) \ + || BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564)) + // These older compilers don't support the overload set creation + // idiom well, so we need to do all the return type calculation + // for the compiler and dispatch through an outer function template + + // A metafunction class that, given a keyword, returns the base + // sublist whose get() function can produce the value for that + // key. + struct key_owner + { + template<class KW> + struct apply + { + typedef typename mpl::eval_if< + boost::is_same<KW, key_type> + , mpl::identity<arg_list<TaggedArg,Next> > + , mpl::apply_wrap1<typename Next::key_owner,KW> + >::type type; + }; + }; + + // Outer indexing operators that dispatch to the right node's + // get() function. + template <class KW> + typename mpl::apply_wrap3<binding, KW, void_, mpl::true_>::type + operator[](keyword<KW> const& x) const + { + typename mpl::apply_wrap1<key_owner, KW>::type const& sublist = *this; + return sublist.get(x); + } + + template <class KW, class Default> + typename mpl::apply_wrap3<binding, KW, Default&, mpl::true_>::type + operator[](default_<KW, Default> x) const + { + typename mpl::apply_wrap1<key_owner, KW>::type const& sublist = *this; + return sublist.get(x); + } + + template <class KW, class F> + typename mpl::apply_wrap3< + binding,KW + , typename result_of0<F>::type + , mpl::true_ + >::type + operator[](lazy_default<KW,F> x) const + { + typename mpl::apply_wrap1<key_owner, KW>::type const& sublist = *this; + return sublist.get(x); + } + + // These just return the stored value; when empty_arg_list is + // reached, indicating no matching argument was passed, the + // default is returned, or if no default_ or lazy_default was + // passed, compilation fails. + reference get(keyword<key_type> const&) const + { + BOOST_MPL_ASSERT_NOT((holds_maybe)); + return arg.value; + } + + template <class Default> + reference get(default_<key_type,Default> const& d) const + { + return get_default(d, holds_maybe()); + } + + template <class Default> + reference get(lazy_default<key_type, Default>) const + { + return arg.value; + } + +#else + + reference operator[](keyword<key_type> const&) const + { + BOOST_MPL_ASSERT_NOT((holds_maybe)); + return arg.value; + } + + template <class Default> + reference operator[](default_<key_type, Default> const& d) const + { + return get_default(d, holds_maybe()); + } + + template <class Default> + reference operator[](lazy_default<key_type, Default>) const + { + return arg.value; + } + + // Builds an overload set including operator[]s defined in base + // classes. + using Next::operator[]; + + // + // End of indexing support + // + + + // + // For parameter_requirements matching this node's key_type, + // return a bool constant wrapper indicating whether the + // requirements are satisfied by TaggedArg. Used only for + // compile-time computation and never really called, so a + // declaration is enough. + // + template <class HasDefault, class Predicate, class ArgPack> + static typename mpl::apply_wrap2< + typename mpl::lambda<Predicate, lambda_tag>::type + , value_type, ArgPack + >::type + satisfies( + parameter_requirements<key_type,Predicate,HasDefault>* + , ArgPack* + ); + + // Builds an overload set including satisfies functions defined + // in base classes. + using Next::satisfies; +#endif + + // Comma operator to compose argument list without using parameters<>. + // Useful for argument lists with undetermined length. + template <class KW, class T2> + arg_list<tagged_argument<KW, T2>, self> + operator,(tagged_argument<KW,T2> x) const + { + return arg_list<tagged_argument<KW,T2>, self>(x, *this); + } + + // MPL sequence support + typedef self type; // Convenience for users + typedef Next tail_type; // For the benefit of iterators + typedef arg_list_tag tag; // For dispatching to sequence intrinsics +}; + +#if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) // ETI workaround +template <> struct arg_list<int,int> {}; +#endif + +// MPL sequence support +template <class ArgumentPack> +struct arg_list_iterator +{ + typedef mpl::forward_iterator_tag category; + + // The incremented iterator + typedef arg_list_iterator<typename ArgumentPack::tail_type> next; + + // dereferencing yields the key type + typedef typename ArgumentPack::key_type type; +}; + +template <> +struct arg_list_iterator<empty_arg_list> {}; + +}} // namespace parameter::aux + +// MPL sequence support +namespace mpl +{ + template <> + struct begin_impl<parameter::aux::arg_list_tag> + { + template <class S> + struct apply + { + typedef parameter::aux::arg_list_iterator<S> type; + }; + }; + + template <> + struct end_impl<parameter::aux::arg_list_tag> + { + template <class> + struct apply + { + typedef parameter::aux::arg_list_iterator<parameter::aux::empty_arg_list> type; + }; + }; +} + +} // namespace boost + +#endif // ARG_LIST_050329_HPP + |