stabilize build system: depends, installer, boost/bdb fixes, cross targets groundwork
This commit is contained in:
@@ -0,0 +1,38 @@
|
||||
/*!
|
||||
@file
|
||||
Defines `boost::hana::id`.
|
||||
|
||||
@copyright Louis Dionne 2013-2017
|
||||
Distributed under the Boost Software License, Version 1.0.
|
||||
(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
|
||||
*/
|
||||
|
||||
#ifndef BOOST_HANA_FUNCTIONAL_ID_HPP
|
||||
#define BOOST_HANA_FUNCTIONAL_ID_HPP
|
||||
|
||||
#include <boost/hana/config.hpp>
|
||||
|
||||
|
||||
BOOST_HANA_NAMESPACE_BEGIN
|
||||
//! @ingroup group-functional
|
||||
//! The identity function -- returns its argument unchanged.
|
||||
//!
|
||||
//! ### Example
|
||||
//! @include example/functional/id.cpp
|
||||
#ifdef BOOST_HANA_DOXYGEN_INVOKED
|
||||
constexpr auto id = [](auto&& x) -> decltype(auto) {
|
||||
return forwarded(x);
|
||||
};
|
||||
#else
|
||||
struct id_t {
|
||||
template <typename T>
|
||||
constexpr T operator()(T&& t) const {
|
||||
return static_cast<T&&>(t);
|
||||
}
|
||||
};
|
||||
|
||||
constexpr id_t id{};
|
||||
#endif
|
||||
BOOST_HANA_NAMESPACE_END
|
||||
|
||||
#endif // !BOOST_HANA_FUNCTIONAL_ID_HPP
|
||||
Reference in New Issue
Block a user