LeechCraft  0.6.70-10870-g558588d6ec
Modular cross-platform feature rich live environment.
applicative.h
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29 
30 #pragma once
31 
32 #include <boost/optional.hpp>
33 
34 namespace LeechCraft
35 {
36 namespace Util
37 {
38  template<typename Applicative>
40 
41  template<typename AF, typename AV>
42  using GSLResult_t = typename InstanceApplicative<AF>::template GSLResult<AV>::Type_t;
43 
44  template<template<typename...> class Applicative, typename... Args, typename T>
45  auto Pure (const T& v)
46  {
47  return InstanceApplicative<Applicative<Args..., T>>::Pure (v);
48  }
49 
50  template<typename Applicative, typename T>
51  auto Pure (const T& v) -> decltype (InstanceApplicative<Applicative>::Pure (v))
52  {
54  }
55 
56  template<typename AF, typename AV>
57  GSLResult_t<AF, AV> GSL (const AF& af, const AV& av)
58  {
59  return InstanceApplicative<AF>::GSL (af, av);
60  }
61 
62  template<typename AF, typename AV>
63  auto operator* (const AF& af, const AV& av) -> decltype (GSL (af, av))
64  {
65  return GSL (af, av);
66  }
67 
68  // Implementations
69  template<typename T>
70  struct InstanceApplicative<boost::optional<T>>
71  {
72  using Type_t = boost::optional<T>;
73 
74  template<typename>
75  struct GSLResult;
76 
77  template<typename V>
78  struct GSLResult<boost::optional<V>>
79  {
80  using Type_t = boost::optional<std::result_of_t<T (V)>>;
81  };
82 
83  template<typename U>
84  static boost::optional<U> Pure (const U& v)
85  {
86  return { v };
87  }
88 
89  template<typename AV>
90  static GSLResult_t<Type_t, AV> GSL (const Type_t& f, const AV& v)
91  {
92  if (!f || !v)
93  return {};
94 
95  return { (*f) (*v) };
96  }
97  };
98 }
99 }
constexpr detail::ExprTree< detail::ExprType::LeafStaticPlaceholder, detail::MemberPtrs< Ptr > > f
Definition: oral.h:931
Definition: prelude.h:39
auto operator*(const AF &af, const AV &av) -> decltype(GSL(af, av))
Definition: applicative.h:63
GSLResult_t< AF, AV > GSL(const AF &af, const AV &av)
Definition: applicative.h:57
auto Pure(const T &v)
Definition: applicative.h:45
static boost::optional< U > Pure(const U &v)
Definition: applicative.h:84
typename InstanceApplicative< AF >::template GSLResult< AV >::Type_t GSLResult_t
Definition: applicative.h:42
auto Pure(const T &v) -> decltype(InstanceApplicative< Applicative >::Pure(v))
Definition: applicative.h:51
static GSLResult_t< Type_t, AV > GSL(const Type_t &f, const AV &v)
Definition: applicative.h:90