598bfd3f
 Hu Chunming
提交_GLIBCXX_USE_CX...
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
/*!
@file
Defines `boost::hana::tap`.
Copyright Louis Dionne 2013-2022
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_TAP_HPP
#define BOOST_HANA_TAP_HPP
#include <boost/hana/fwd/tap.hpp>
#include <boost/hana/concept/monad.hpp>
#include <boost/hana/config.hpp>
#include <boost/hana/core/dispatch.hpp>
#include <boost/hana/functional/partial.hpp>
#include <boost/hana/lift.hpp>
namespace boost { namespace hana {
//! @cond
template <typename M>
template <typename F>
constexpr auto tap_t<M>::operator()(F&& f) const {
#ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
static_assert(hana::Monad<M>::value,
"hana::tap<M> requires 'M' to be a Monad");
#endif
using Tap = BOOST_HANA_DISPATCH_IF(tap_impl<M>,
hana::Monad<M>::value
);
return Tap::apply(static_cast<F&&>(f));
}
//! @endcond
namespace detail {
template <typename M>
struct tap_helper {
template <typename F, typename X>
constexpr auto operator()(F&& f, X&& x) const {
(void)static_cast<F&&>(f)(x);
return hana::lift<M>(static_cast<X&&>(x));
}
};
}
template <typename M, bool condition>
struct tap_impl<M, when<condition>> : default_ {
template <typename F>
static constexpr auto apply(F&& f)
{ return hana::partial(detail::tap_helper<M>{}, static_cast<F&&>(f)); }
};
}} // end namespace boost::hana
#endif // !BOOST_HANA_TAP_HPP
|
