diff options
Diffstat (limited to 'boost/variant/get.hpp')
| -rw-r--r-- | boost/variant/get.hpp | 159 |
1 files changed, 151 insertions, 8 deletions
diff --git a/boost/variant/get.hpp b/boost/variant/get.hpp index e3302c0213..3188a6547a 100644 --- a/boost/variant/get.hpp +++ b/boost/variant/get.hpp @@ -3,8 +3,8 @@ // See http://www.boost.org for updates, documentation, and revision history. //----------------------------------------------------------------------------- // -// Copyright (c) 2003 -// Eric Friedman, Itay Maman +// Copyright (c) 2003 Eric Friedman, Itay Maman +// Copyright (c) 2014 Antony Polukhin // // Distributed under the Boost Software License, Version 1.0. (See // accompanying file LICENSE_1_0.txt or copy at @@ -17,9 +17,11 @@ #include "boost/config.hpp" #include "boost/detail/workaround.hpp" +#include "boost/static_assert.hpp" #include "boost/throw_exception.hpp" #include "boost/utility/addressof.hpp" #include "boost/variant/variant_fwd.hpp" +#include "boost/variant/detail/element_index.hpp" #include "boost/type_traits/add_reference.hpp" #include "boost/type_traits/add_pointer.hpp" @@ -95,10 +97,13 @@ public: // visitor interfaces # endif #endif +///////////////////////////////////////////////////////////////////////////////////////////////////////////// +// relaxed_get<U>(variant) methods +// template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > inline typename add_pointer<U>::type -get( +relaxed_get( boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) ) BOOST_NOEXCEPT @@ -113,7 +118,7 @@ get( template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > inline typename add_pointer<const U>::type -get( +relaxed_get( const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) ) BOOST_NOEXCEPT @@ -128,13 +133,13 @@ get( template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > inline typename add_reference<U>::type -get( +relaxed_get( boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) ) { typedef typename add_pointer<U>::type U_ptr; - U_ptr result = get<U>(&operand); + U_ptr result = relaxed_get<U>(&operand); if (!result) boost::throw_exception(bad_get()); @@ -144,19 +149,157 @@ get( template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > inline typename add_reference<const U>::type -get( +relaxed_get( const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) ) { typedef typename add_pointer<const U>::type U_ptr; - U_ptr result = get<const U>(&operand); + U_ptr result = relaxed_get<const U>(&operand); if (!result) boost::throw_exception(bad_get()); return *result; } + + +///////////////////////////////////////////////////////////////////////////////////////////////////////////// +// strict_get<U>(variant) methods +// +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_pointer<U>::type +strict_get( + boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) BOOST_NOEXCEPT +{ + BOOST_STATIC_ASSERT_MSG( + (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value), + "boost::variant does not contain specified type U, " + "call to boost::get<U>(boost::variant<T...>*) will always return NULL" + ); + + return relaxed_get<U>(operand); +} + +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_pointer<const U>::type +strict_get( + const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) BOOST_NOEXCEPT +{ + BOOST_STATIC_ASSERT_MSG( + (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, const U >::value), + "boost::variant does not contain specified type U, " + "call to boost::get<U>(const boost::variant<T...>*) will always return NULL" + ); + + return relaxed_get<U>(operand); +} + +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_reference<U>::type +strict_get( + boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) +{ + BOOST_STATIC_ASSERT_MSG( + (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, U >::value), + "boost::variant does not contain specified type U, " + "call to boost::get<U>(boost::variant<T...>&) will always throw boost::bad_get exception" + ); + + return relaxed_get<U>(operand); +} + +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_reference<const U>::type +strict_get( + const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) +{ + BOOST_STATIC_ASSERT_MSG( + (boost::detail::variant::holds_element<boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >, const U >::value), + "boost::variant does not contain specified type U, " + "call to boost::get<U>(const boost::variant<T...>&) will always throw boost::bad_get exception" + ); + + return relaxed_get<U>(operand); +} + +///////////////////////////////////////////////////////////////////////////////////////////////////////////// +// get<U>(variant) methods +// + +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_pointer<U>::type +get( + boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) BOOST_NOEXCEPT +{ +#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT + return relaxed_get<U>(operand); +#else + return strict_get<U>(operand); +#endif + +} + +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_pointer<const U>::type +get( + const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >* operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) BOOST_NOEXCEPT +{ +#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT + return relaxed_get<U>(operand); +#else + return strict_get<U>(operand); +#endif +} + +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_reference<U>::type +get( + boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) +{ +#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT + return relaxed_get<U>(operand); +#else + return strict_get<U>(operand); +#endif +} + +template <typename U, BOOST_VARIANT_ENUM_PARAMS(typename T) > +inline + typename add_reference<const U>::type +get( + const boost::variant< BOOST_VARIANT_ENUM_PARAMS(T) >& operand + BOOST_VARIANT_AUX_GET_EXPLICIT_TEMPLATE_TYPE(U) + ) +{ +#ifdef BOOST_VARIANT_USE_RELAXED_GET_BY_DEFAULT + return relaxed_get<U>(operand); +#else + return strict_get<U>(operand); +#endif +} + } // namespace boost #endif // BOOST_VARIANT_GET_HPP |