LeechCraft  0.6.70-6645-gcd10d7e
Modular cross-platform feature rich live environment.
functor.h
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29 
30 #pragma once
31 
32 #include <boost/optional.hpp>
33 #include "oldcppkludges.h"
34 
35 namespace LeechCraft
36 {
37 namespace Util
38 {
39  template<typename T>
41 
42  template<typename T, typename F>
44 
45  template<typename T, typename F>
46  FmapResult_t<T, F> Fmap (const T& t, const F& f)
47  {
48  return InstanceFunctor<T>::Apply (t, f);
49  }
50 
51  template<typename MF, typename F>
52  auto operator* (const F& f, const MF& value) -> decltype (Fmap (value, f))
53  {
54  return Fmap (value, f);
55  }
56 
57  // Implementations
58  template<typename T>
59  struct InstanceFunctor<boost::optional<T>>
60  {
61  template<typename F>
62  using FmapResult_t = boost::optional<Decay_t<ResultOf_t<F (T)>>>;
63 
64  template<typename F>
65  static FmapResult_t<F> Apply (const boost::optional<T>& t, const F& f)
66  {
67  if (!t)
68  return {};
69 
70  return { Invoke (f, *t) };
71  }
72  };
73 }
74 }
auto operator*(const AF &af, const AV &av) -> decltype(GSL(af, av))
Definition: applicative.h:64
FmapResult_t< T, F > Fmap(const T &t, const F &f)
Definition: functor.h:46
struct LeechCraft::Util::@2 Apply
boost::optional< Decay_t< ResultOf_t< F(T)>>> FmapResult_t
Definition: functor.h:62
static FmapResult_t< F > Apply(const boost::optional< T > &t, const F &f)
Definition: functor.h:65
auto Invoke(F &&f, Args &&...args) -> decltype(std::forward< F >(f)(std::forward< Args >(args)...))
Definition: oldcppkludges.h:39
typename InstanceFunctor< T >::template FmapResult_t< F > FmapResult_t
Definition: functor.h:43