Brian Silverman | 4a2409e | 2018-08-04 23:24:02 -0700 | [diff] [blame^] | 1 | [/ |
| 2 | Copyright 2010 John Maddock. |
| 3 | Distributed under the Boost Software License, Version 1.0. |
| 4 | (See accompanying file LICENSE_1_0.txt or copy at |
| 5 | http://www.boost.org/LICENSE_1_0.txt). |
| 6 | ] |
| 7 | |
| 8 | [section:add_lvalue_reference add_lvalue_reference] |
| 9 | |
| 10 | template <class T> |
| 11 | struct add_lvalue_reference |
| 12 | { |
| 13 | typedef __below type; |
| 14 | }; |
| 15 | |
| 16 | template <class T> using add_lvalue_reference_t = typename add_lvalue_reference<T>::type; // C++11 and above |
| 17 | |
| 18 | __type If `T` names an object or function type then the member typedef `type` |
| 19 | shall name `T&`; otherwise, if `T` names a type ['rvalue reference to U] then |
| 20 | the member typedef type shall name `U&`; otherwise, type shall name `T`. |
| 21 | |
| 22 | __std_ref 20.7.6.2. |
| 23 | |
| 24 | __header ` #include <boost/type_traits/add_lvalue_reference.hpp>` or ` #include <boost/type_traits.hpp>` |
| 25 | |
| 26 | [table Examples |
| 27 | |
| 28 | [ [Expression] [Result Type]] |
| 29 | |
| 30 | [[`add_lvalue_reference<int>::type`][`int&`]] |
| 31 | |
| 32 | [[`add_lvalue_reference<int const&>::type`] [`int const&`]] |
| 33 | |
| 34 | [[`add_lvalue_reference<int*>::type`] [`int*&`]] |
| 35 | |
| 36 | [[`add_lvalue_reference<int*&>::type`] [`int*&`]] |
| 37 | |
| 38 | [[`add_lvalue_reference<int&&>::type`][`int&`]] |
| 39 | |
| 40 | [[`add_lvalue_reference<void>::type`][`void`]] |
| 41 | |
| 42 | ] |
| 43 | |
| 44 | [all_compilers] |
| 45 | |
| 46 | [endsect] |
| 47 | |