feedc0de/boost_core
1
0
Fork 0
forked from boostorg/core
Code Pull Requests Activity

Make pointer_traits SFINAE friendly

Browse Source
This commit is contained in:
Glen Fernandes
2021-12-12 19:03:57 -05:00
parent 6da7958281
commit 0e62373aa2
7 changed files with 397 additions and 150 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
test/Jamfile.v2
View File

@@ -189,6 +189,9 @@ run pointer_traits_element_type_test.cpp ;
run pointer_traits_difference_type_test.cpp ;
run pointer_traits_rebind_test.cpp ;
run pointer_traits_pointer_to_test.cpp ;
run pointer_traits_sfinae_test.cpp ;
run pointer_traits_rebind_sfinae_test.cpp ;
run pointer_traits_pointer_to_sfinae_test.cpp ;
run to_address_test.cpp ;
run exchange_test.cpp ;

75
test/pointer_traits_pointer_to_sfinae_test.cpp Normal file
View File

@@ -0,0 +1,75 @@
/*
Copyright 2021 Glen Joseph Fernandes
(glenjofe@gmail.com)
Distributed under the Boost Software License, Version 1.0.
(http://www.boost.org/LICENSE_1_0.txt)
*/
#include <boost/config.hpp>
#if !defined(BOOST_NO_CXX11_DECLTYPE_N3276) || !defined(BOOST_MSVC)
#include <boost/core/pointer_traits.hpp>
#include <boost/core/lightweight_test.hpp>
#if !defined(BOOST_NO_CXX11_DECLTYPE_N3276)
template<class T>
class has_pointer_to {
template<class>
struct result {
char one;
char two;
};
template<class O>
static auto check(int) -> result<decltype(O::pointer_to)>;
template<class O>
static char check(long);
public:
static const bool value = sizeof(check<T>(0)) != 1;
};
#else
template<class T>
class has_pointer_to {
template<int>
struct result {
char one;
char two;
};
template<class O>
static result<sizeof(&O::pointer_to)> check(int);
template<class>
static char check(long);
public:
static const bool value = sizeof(check<T>(0)) != 1;
};
#endif
struct P1 { };
struct P2 {
typedef int element_type;
};
struct P3 {
typedef void element_type;
};
int main()
{
BOOST_TEST((!has_pointer_to<boost::pointer_traits<P1> >::value));
BOOST_TEST(has_pointer_to<boost::pointer_traits<P2> >::value);
BOOST_TEST(!has_pointer_to<boost::pointer_traits<P3> >::value);
BOOST_TEST(has_pointer_to<boost::pointer_traits<int*> >::value);
BOOST_TEST(!has_pointer_to<boost::pointer_traits<void*> >::value);
return boost::report_errors();
}
#else
int main()
{
return 0;
}
#endif

83
test/pointer_traits_rebind_sfinae_test.cpp Normal file
View File

@@ -0,0 +1,83 @@
/*
Copyright 2021 Glen Joseph Fernandes
(glenjofe@gmail.com)
Distributed under the Boost Software License, Version 1.0.
(http://www.boost.org/LICENSE_1_0.txt)
*/
#include <boost/config.hpp>
#if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES) && \
(!defined(BOOST_GCC) || (BOOST_GCC >= 40800)) && \
(!defined(BOOST_MSVC) || (BOOST_MSVC >= 1900))
#include <boost/core/pointer_traits.hpp>
#include <boost/core/lightweight_test.hpp>
template<class>
struct valid {
typedef void type;
};
#if !defined(BOOST_GCC) || (BOOST_GCC >= 50000)
template<class, class, class = void>
struct has_rebind {
static const bool value = false;
};
template<class T, class U>
struct has_rebind<T, U,
typename valid<typename T::template rebind<U> >::type> {
static const bool value = true;
};
#else
template<template<class> class T, class U>
using defer = T<U>;
template<class T, class U>
using rebind = defer<T::template rebind, U>;
template<class, class, template<class, class> class = rebind, class = void>
struct has_rebind {
static const bool value = false;
};
template<class T, class U, template<class, class> class R>
struct has_rebind<T, U, R, typename valid<R<T, U> >::type> {
static const bool value = true;
};
#endif
struct P1 { };
struct P2 {
typedef int element_type;
};
struct P3 {
typedef int element_type;
template<class>
struct rebind { };
};
template<class T>
struct S {
typedef T element_type;
};
typedef S<int> P4;
int main()
{
BOOST_TEST((!has_rebind<boost::pointer_traits<P1>, char>::value));
BOOST_TEST((!has_rebind<boost::pointer_traits<P2>, char>::value));
BOOST_TEST((has_rebind<boost::pointer_traits<P3>, char>::value));
BOOST_TEST((has_rebind<boost::pointer_traits<P4>, char>::value));
BOOST_TEST((has_rebind<boost::pointer_traits<int*>, char>::value));
return boost::report_errors();
}
#else
int main()
{
return 0;
}
#endif

101
test/pointer_traits_sfinae_test.cpp Normal file
View File

@@ -0,0 +1,101 @@
/*
Copyright 2021 Glen Joseph Fernandes
(glenjofe@gmail.com)
Distributed under the Boost Software License, Version 1.0.
(http://www.boost.org/LICENSE_1_0.txt)
*/
#include <boost/core/pointer_traits.hpp>
#include <boost/core/lightweight_test.hpp>
template<class>
struct valid {
typedef void type;
};
template<class, class = void>
struct has_pointer {
static const bool value = false;
};
template<class T>
struct has_pointer<T, typename valid<typename T::pointer>::type> {
static const bool value = true;
};
template<class, class = void>
struct has_element_type {
static const bool value = false;
};
template<class T>
struct has_element_type<T, typename valid<typename T::element_type>::type> {
static const bool value = true;
};
template<class, class = void>
struct has_difference_type {
static const bool value = false;
};
template<class T>
struct has_difference_type<T,
typename valid<typename T::difference_type>::type> {
static const bool value = true;
};
template<class, class, class = void>
struct has_rebind_to_type {
static const bool value = false;
};
template<class T, class U>
struct has_rebind_to_type<T, U,
typename valid<typename T::template rebind_to<U>::type>::type> {
static const bool value = true;
};
struct P1 { };
struct P2 {
typedef int element_type;
};
struct P3 {
typedef int element_type;
template<class>
struct rebind { };
};
template<class T>
struct S {
typedef T element_type;
};
typedef S<int> P4;
int main()
{
BOOST_TEST(!has_pointer<boost::pointer_traits<P1> >::value);
BOOST_TEST(!has_element_type<boost::pointer_traits<P1> >::value);
BOOST_TEST(!has_difference_type<boost::pointer_traits<P1> >::value);
BOOST_TEST((!has_rebind_to_type<boost::pointer_traits<P1>, char>::value));
BOOST_TEST(has_pointer<boost::pointer_traits<P2> >::value);
BOOST_TEST(has_element_type<boost::pointer_traits<P2> >::value);
BOOST_TEST(has_difference_type<boost::pointer_traits<P2> >::value);
BOOST_TEST((!has_rebind_to_type<boost::pointer_traits<P2>, char>::value));
BOOST_TEST(has_pointer<boost::pointer_traits<P3> >::value);
BOOST_TEST(has_element_type<boost::pointer_traits<P3> >::value);
BOOST_TEST(has_difference_type<boost::pointer_traits<P3> >::value);
BOOST_TEST((has_rebind_to_type<boost::pointer_traits<P3>, char>::value));
BOOST_TEST(has_pointer<boost::pointer_traits<P4> >::value);
BOOST_TEST(has_element_type<boost::pointer_traits<P4> >::value);
BOOST_TEST(has_difference_type<boost::pointer_traits<P4> >::value);
BOOST_TEST((has_rebind_to_type<boost::pointer_traits<P4>, char>::value));
BOOST_TEST(has_pointer<boost::pointer_traits<int*> >::value);
BOOST_TEST(has_element_type<boost::pointer_traits<int*> >::value);
BOOST_TEST(has_difference_type<boost::pointer_traits<int*> >::value);
BOOST_TEST((has_rebind_to_type<boost::pointer_traits<int*>, char>::value));
return boost::report_errors();
}

72
test/to_address_test.cpp
View File

@@ -13,9 +13,11 @@ class P1 {
public:
explicit P1(T* p)
: p_(p) { }
T* operator->() const BOOST_NOEXCEPT {
return p_;
}
private:
T* p_;
};
@@ -25,9 +27,11 @@ class P2 {
public:
explicit P2(T* p)
: p_(p) { }
P1<T> operator->() const BOOST_NOEXCEPT {
return p_;
}
private:
P1<T> p_;
};
@@ -38,20 +42,24 @@ class P3 {
public:
explicit P3(T* p)
: p_(p) { }
T* get() const BOOST_NOEXCEPT {
return p_;
}
private:
T* p_;
};
namespace boost {
template<class T>
struct pointer_traits<P3<T> > {
static T* to_address(const P3<T>& p) BOOST_NOEXCEPT {
return p.get();
}
};
} /* boost */
template<class T>
@@ -59,77 +67,29 @@ class P4 {
public:
explicit P4(T* p)
: p_(p) { }
T* operator->() const BOOST_NOEXCEPT {
return 0;
}
T* get() const BOOST_NOEXCEPT {
return p_;
}
private:
int* p_;
};
namespace boost {
template<class T>
struct pointer_traits<P4<T> > {
static T* to_address(const P4<T>& p) BOOST_NOEXCEPT {
return p.get();
}
};
} /* boost */
#if !defined(BOOST_NO_CXX11_POINTER_TRAITS)
template<class T>
class P5 {
public:
explicit P5(T* p)
: p_(p) { }
T* get() const BOOST_NOEXCEPT {
return p_;
}
private:
T* p_;
};
namespace std {
template<class T>
struct pointer_traits<P5<T> > {
static T* to_address(const P5<T>& p) BOOST_NOEXCEPT {
return p.get();
}
};
} /* std */
template<class T>
class P6 {
public:
explicit P6(T* p)
: p_(p) { }
T* get() const BOOST_NOEXCEPT {
return p_;
}
private:
T* p_;
};
namespace boost {
template<class T>
struct pointer_traits<P6<T> > {
static T* to_address(const P6<T>& p) BOOST_NOEXCEPT {
return p.get();
}
};
} /* boost */
namespace std {
template<class T>
struct pointer_traits<P6<T> > {
static T* to_address(const P6<T>& /*p*/) BOOST_NOEXCEPT {
return 0;
}
};
} /* std */
#endif
#endif
int main()
@@ -147,12 +107,6 @@ int main()
BOOST_TEST(boost::to_address(p3) == &i);
P4<int> p4(&i);
BOOST_TEST(boost::to_address(p4) == &i);
#if !defined(BOOST_NO_CXX11_POINTER_TRAITS)
P5<int> p5(&i);
BOOST_TEST(boost::to_address(p5) == &i);
P6<int> p6(&i);
BOOST_TEST(boost::to_address(p6) == &i);
#endif
#endif
return boost::report_errors();
}