LeechCraft  0.6.70-6645-gcd10d7e
Modular cross-platform feature rich live environment.
applicative.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 Applicative>
41 
42  template<typename AF, typename AV>
43  using GSLResult_t = typename InstanceApplicative<AF>::template GSLResult<AV>::Type_t;
44 
45  template<template<typename...> class Applicative, typename... Args, typename T>
46  Applicative<Args..., T> Pure (const T& v)
47  {
48  return InstanceApplicative<Applicative<Args..., T>>::Pure (v);
49  }
50 
51  template<typename Applicative, typename T>
52  auto Pure (const T& v) -> decltype (InstanceApplicative<Applicative>::Pure (v))
53  {
55  }
56 
57  template<typename AF, typename AV>
58  GSLResult_t<AF, AV> GSL (const AF& af, const AV& av)
59  {
60  return InstanceApplicative<AF>::GSL (af, av);
61  }
62 
63  template<typename AF, typename AV>
64  auto operator* (const AF& af, const AV& av) -> decltype (GSL (af, av))
65  {
66  return GSL (af, av);
67  }
68 
69  // Implementations
70  template<typename T>
71  struct InstanceApplicative<boost::optional<T>>
72  {
73  using Type_t = boost::optional<T>;
74 
75  template<typename>
76  struct GSLResult;
77 
78  template<typename V>
79  struct GSLResult<boost::optional<V>>
80  {
81  using Type_t = boost::optional<ResultOf_t<T (V)>>;
82  };
83 
84  template<typename U>
85  static boost::optional<U> Pure (const U& v)
86  {
87  return { v };
88  }
89 
90  template<typename AV>
91  static GSLResult_t<Type_t, AV> GSL (const Type_t& f, const AV& v)
92  {
93  if (!f || !v)
94  return {};
95 
96  return { (*f) (*v) };
97  }
98  };
99 }
100 }
auto operator*(const AF &af, const AV &av) -> decltype(GSL(af, av))
Definition: applicative.h:64
GSLResult_t< AF, AV > GSL(const AF &af, const AV &av)
Definition: applicative.h:58
static boost::optional< U > Pure(const U &v)
Definition: applicative.h:85
Applicative< Args..., T > Pure(const T &v)
Definition: applicative.h:46
typename InstanceApplicative< AF >::template GSLResult< AV >::Type_t GSLResult_t
Definition: applicative.h:43
auto Pure(const T &v) -> decltype(InstanceApplicative< Applicative >::Pure(v))
Definition: applicative.h:52
static GSLResult_t< Type_t, AV > GSL(const Type_t &f, const AV &v)
Definition: applicative.h:91