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Diffstat (limited to '3rdParty/Boost/src/boost/type_traits/detail/has_postfix_operator.hpp')
-rw-r--r-- | 3rdParty/Boost/src/boost/type_traits/detail/has_postfix_operator.hpp | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/3rdParty/Boost/src/boost/type_traits/detail/has_postfix_operator.hpp b/3rdParty/Boost/src/boost/type_traits/detail/has_postfix_operator.hpp new file mode 100644 index 0000000..5c52b07 --- /dev/null +++ b/3rdParty/Boost/src/boost/type_traits/detail/has_postfix_operator.hpp @@ -0,0 +1,202 @@ +// (C) Copyright 2009-2011 Frederic Bron, Robert Stewart, Steven Watanabe & Roman Perepelitsa. +// +// Use, modification and distribution are 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). +// +// See http://www.boost.org/libs/type_traits for most recent version including documentation. + +#include <boost/config.hpp> +#include <boost/type_traits/ice.hpp> +#include <boost/type_traits/integral_constant.hpp> +#include <boost/type_traits/is_const.hpp> +#include <boost/type_traits/is_fundamental.hpp> +#include <boost/type_traits/is_pointer.hpp> +#include <boost/type_traits/is_same.hpp> +#include <boost/type_traits/is_void.hpp> +#include <boost/type_traits/remove_cv.hpp> +#include <boost/type_traits/remove_pointer.hpp> +#include <boost/type_traits/remove_reference.hpp> + +// should be the last #include +#include <boost/type_traits/detail/bool_trait_def.hpp> + +// avoid warnings +#if defined(__GNUC__) && ((__GNUC__==3 && __GNUC_MINOR__>=1) || (__GNUC__>3)) +# pragma GCC system_header +#elif defined(BOOST_MSVC) +# pragma warning ( push ) +# pragma warning ( disable : 4244 4913 ) +#endif + +namespace boost { +namespace detail { + +// This namespace ensures that argument-dependent name lookup does not mess things up. +namespace BOOST_JOIN(BOOST_TT_TRAIT_NAME,_impl) { + +// 1. a function to have an instance of type T without requiring T to be default +// constructible +template <typename T> T &make(); + + +// 2. we provide our operator definition for types that do not have one already + +// a type returned from operator BOOST_TT_TRAIT_OP when no such operator is +// found in the type's own namespace (our own operator is used) so that we have +// a means to know that our operator was used +struct no_operator { }; + +// this class allows implicit conversions and makes the following operator +// definition less-preferred than any other such operators that might be found +// via argument-dependent name lookup +struct any { template <class T> any(T const&); }; + +// when operator BOOST_TT_TRAIT_OP is not available, this one is used +no_operator operator BOOST_TT_TRAIT_OP (const any&, int); + + +// 3. checks if the operator returns void or not +// conditions: Lhs!=void + +// we first redefine "operator," so that we have no compilation error if +// operator BOOST_TT_TRAIT_OP returns void and we can use the return type of +// (lhs BOOST_TT_TRAIT_OP, returns_void_t()) to deduce if +// operator BOOST_TT_TRAIT_OP returns void or not: +// - operator BOOST_TT_TRAIT_OP returns void -> (lhs BOOST_TT_TRAIT_OP, returns_void_t()) returns returns_void_t +// - operator BOOST_TT_TRAIT_OP returns !=void -> (lhs BOOST_TT_TRAIT_OP, returns_void_t()) returns int +struct returns_void_t { }; +template <typename T> int operator,(const T&, returns_void_t); +template <typename T> int operator,(const volatile T&, returns_void_t); + +// this intermediate trait has member value of type bool: +// - value==true -> operator BOOST_TT_TRAIT_OP returns void +// - value==false -> operator BOOST_TT_TRAIT_OP does not return void +template < typename Lhs > +struct operator_returns_void { + // overloads of function returns_void make the difference + // yes_type and no_type have different size by construction + static ::boost::type_traits::yes_type returns_void(returns_void_t); + static ::boost::type_traits::no_type returns_void(int); + BOOST_STATIC_CONSTANT(bool, value = (sizeof(::boost::type_traits::yes_type)==sizeof(returns_void((make<Lhs>() BOOST_TT_TRAIT_OP,returns_void_t()))))); +}; + + +// 4. checks if the return type is Ret or Ret==dont_care +// conditions: Lhs!=void + +struct dont_care { }; + +template < typename Lhs, typename Ret, bool Returns_void > +struct operator_returns_Ret; + +template < typename Lhs > +struct operator_returns_Ret < Lhs, dont_care, true > { + BOOST_STATIC_CONSTANT(bool, value = true); +}; + +template < typename Lhs > +struct operator_returns_Ret < Lhs, dont_care, false > { + BOOST_STATIC_CONSTANT(bool, value = true); +}; + +template < typename Lhs > +struct operator_returns_Ret < Lhs, void, true > { + BOOST_STATIC_CONSTANT(bool, value = true); +}; + +template < typename Lhs > +struct operator_returns_Ret < Lhs, void, false > { + BOOST_STATIC_CONSTANT(bool, value = false); +}; + +template < typename Lhs, typename Ret > +struct operator_returns_Ret < Lhs, Ret, true > { + BOOST_STATIC_CONSTANT(bool, value = false); +}; + +// otherwise checks if it is convertible to Ret using the sizeof trick +// based on overload resolution +// condition: Ret!=void and Ret!=dont_care and the operator does not return void +template < typename Lhs, typename Ret > +struct operator_returns_Ret < Lhs, Ret, false > { + static ::boost::type_traits::yes_type is_convertible_to_Ret(Ret); // this version is preferred for types convertible to Ret + static ::boost::type_traits::no_type is_convertible_to_Ret(...); // this version is used otherwise + + BOOST_STATIC_CONSTANT(bool, value = (sizeof(is_convertible_to_Ret(make<Lhs>() BOOST_TT_TRAIT_OP))==sizeof(::boost::type_traits::yes_type))); +}; + + +// 5. checks for operator existence +// condition: Lhs!=void + +// checks if our definition of operator BOOST_TT_TRAIT_OP is used or an other +// existing one; +// this is done with redefinition of "operator," that returns no_operator or has_operator +struct has_operator { }; +no_operator operator,(no_operator, has_operator); + +template < typename Lhs > +struct operator_exists { + static ::boost::type_traits::yes_type check(has_operator); // this version is preferred when operator exists + static ::boost::type_traits::no_type check(no_operator); // this version is used otherwise + + BOOST_STATIC_CONSTANT(bool, value = (sizeof(check(((make<Lhs>() BOOST_TT_TRAIT_OP),make<has_operator>())))==sizeof(::boost::type_traits::yes_type))); +}; + + +// 6. main trait: to avoid any compilation error, this class behaves +// differently when operator BOOST_TT_TRAIT_OP(Lhs) is forbidden by the +// standard. +// Forbidden_if is a bool that is: +// - true when the operator BOOST_TT_TRAIT_OP(Lhs) is forbidden by the standard +// (would yield compilation error if used) +// - false otherwise +template < typename Lhs, typename Ret, bool Forbidden_if > +struct trait_impl1; + +template < typename Lhs, typename Ret > +struct trait_impl1 < Lhs, Ret, true > { + BOOST_STATIC_CONSTANT(bool, value = false); +}; + +template < typename Lhs, typename Ret > +struct trait_impl1 < Lhs, Ret, false > { + BOOST_STATIC_CONSTANT(bool, + value = ( + ::boost::type_traits::ice_and< + operator_exists < Lhs >::value, + operator_returns_Ret < Lhs, Ret, operator_returns_void < Lhs >::value >::value + >::value + ) + ); +}; + +// specialization needs to be declared for the special void case +template < typename Ret > +struct trait_impl1 < void, Ret, false > { + BOOST_STATIC_CONSTANT(bool, value = false); +}; + +// defines some typedef for convenience +template < typename Lhs, typename Ret > +struct trait_impl { + typedef typename ::boost::remove_reference<Lhs>::type Lhs_noref; + typedef typename ::boost::remove_cv<Lhs_noref>::type Lhs_nocv; + typedef typename ::boost::remove_cv< typename ::boost::remove_reference< typename ::boost::remove_pointer<Lhs_noref>::type >::type >::type Lhs_noptr; + BOOST_STATIC_CONSTANT(bool, value = (trait_impl1 < Lhs_noref, Ret, BOOST_TT_FORBIDDEN_IF >::value)); +}; + +} // namespace impl +} // namespace detail + +// this is the accessible definition of the trait to end user +BOOST_TT_AUX_BOOL_TRAIT_DEF2(BOOST_TT_TRAIT_NAME, Lhs, Ret=::boost::detail::BOOST_JOIN(BOOST_TT_TRAIT_NAME,_impl)::dont_care, (::boost::detail::BOOST_JOIN(BOOST_TT_TRAIT_NAME,_impl)::trait_impl< Lhs, Ret >::value)) + +} // namespace boost + +#if defined(BOOST_MSVC) +# pragma warning ( pop ) +#endif + +#include <boost/type_traits/detail/bool_trait_undef.hpp> |