Implement n3584 - Addressing Tuples by Type

llvm-svn: 186237

libcxx/include/tuple

@@ -94,6 +94,13 @@ template <intsize_t I, class... T>
     typename tuple_element<I, tuple<T...>>::type&&
     get(tuple<T...>&&) noexcept;
 
+template <class T1, class... T>
+    constexpr T1& get(tuple<T...>&) noexcept;  // C++14
+template <class T1, class... T>
+    constexpr T1 const& get(const tuple<T...>&) noexcept;   // C++14
+template <class T1, class... T>
+    constexpr T1&& get(tuple<T...>&&) noexcept;   // C++14
+
 // 20.4.1.6, relational operators:
 template<class... T, class... U> bool operator==(const tuple<T...>&, const tuple<U...>&);
 template<class... T, class... U> bool operator<(const tuple<T...>&, const tuple<U...>&);
@@ -783,6 +790,64 @@ get(tuple<_Tp...>&& __t) _NOEXCEPT
              static_cast<__tuple_leaf<_Ip, type>&&>(__t.base_).get());
 }
 
+#if _LIBCPP_STD_VER > 11
+// get by type
+template <typename _T1, size_t _Idx, typename... _Args>
+struct __find_exactly_one_t_helper;
+
+// -- find exactly one
+template <typename _T1, size_t _Idx, typename... _Args>
+struct __find_exactly_one_t_checker {
+    static constexpr size_t value = _Idx;
+//  Check the rest of the list to make sure there's only one
+    static_assert ( __find_exactly_one_t_helper<_T1, 0, _Args...>::value == -1, "type can only occur once in type list" );
+    };
+
+
+template <typename _T1, size_t _Idx>
+struct __find_exactly_one_t_helper <_T1, _Idx> {
+    static constexpr size_t value = -1;
+    };
+
+template <typename _T1, size_t _Idx, typename _Head, typename... _Args>
+struct __find_exactly_one_t_helper <_T1, _Idx, _Head, _Args...> {
+    static constexpr size_t value =
+        std::conditional<
+            std::is_same<_T1, _Head>::value,
+            __find_exactly_one_t_checker<_T1, _Idx,   _Args...>,
+            __find_exactly_one_t_helper <_T1, _Idx+1, _Args...>
+        >::type::value;
+    };
+
+template <typename _T1, typename... _Args>
+struct __find_exactly_one_t {
+    static constexpr size_t value = __find_exactly_one_t_helper<_T1, 0, _Args...>::value;
+    static_assert ( value != -1, "type not found in type list" );
+    };
+
+template <class _T1, class... _Args>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr _T1& get(tuple<_Args...>& __tup) noexcept
+{
+    return _VSTD::get<__find_exactly_one_t<_T1, _Args...>::value>(__tup);
+}
+
+template <class _T1, class... _Args>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr _T1 const& get(tuple<_Args...> const& __tup) noexcept
+{
+    return _VSTD::get<__find_exactly_one_t<_T1, _Args...>::value>(__tup);
+}
+
+template <class _T1, class... _Args>
+inline _LIBCPP_INLINE_VISIBILITY
+constexpr _T1&& get(tuple<_Args...>&& __tup) noexcept
+{
+    return _VSTD::get<__find_exactly_one_t<_T1, _Args...>::value>(_VSTD::move<tuple<_Args...>>(__tup));
+}
+
+#endif
+
 // tie
 
 template <class ..._Tp>

libcxx/include/utility

@@ -117,6 +117,15 @@ template<size_t I, class T1, class T2>
     typename tuple_element<I, std::pair<T1, T2> >::type&&
     get(std::pair<T1, T2>&&) noexcept;
 
+template<class T1, class T2>
+    constexpr T1& get(std::pair<T1, T2>&) noexcept; // C++14
+
+template<size_t I, class T1, class T2>
+    constexpr T1 const& get(std::pair<T1, T2> const &) noexcept; // C++14
+
+template<size_t I, class T1, class T2>
+    constexpr T1&& get(std::pair<T1, T2>&&) noexcept; // C++14
+
 // C++14
 
 template<class T, T... I>
@@ -601,6 +610,51 @@ get(pair<_T1, _T2>&& __p) _NOEXCEPT
 
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
+#if _LIBCPP_STD_VER > 11
+template <class _T1, class _T2>
+_LIBCPP_INLINE_VISIBILITY inline
+constexpr _T1 & get(pair<_T1, _T2>& __p) _NOEXCEPT
+{
+	return __get_pair<0>::get(__p);
+}
+
+template <class _T1, class _T2>
+_LIBCPP_INLINE_VISIBILITY inline
+constexpr _T1 const & get(pair<_T1, _T2> const& __p) _NOEXCEPT
+{
+	return __get_pair<0>::get(__p);
+}
+
+template <class _T1, class _T2>
+_LIBCPP_INLINE_VISIBILITY inline
+constexpr _T1 && get(pair<_T1, _T2>&& __p) _NOEXCEPT
+{
+	return __get_pair<0>::get(_VSTD::move(__p));
+}
+
+template <class _T1, class _T2>
+_LIBCPP_INLINE_VISIBILITY inline
+constexpr _T1 & get(pair<_T2, _T1>& __p) _NOEXCEPT
+{
+	return __get_pair<1>::get(__p);
+}
+
+template <class _T1, class _T2>
+_LIBCPP_INLINE_VISIBILITY inline
+constexpr _T1 const & get(pair<_T2, _T1> const& __p) _NOEXCEPT
+{
+	return __get_pair<1>::get(__p);
+}
+
+template <class _T1, class _T2>
+_LIBCPP_INLINE_VISIBILITY inline
+constexpr _T1 && get(pair<_T2, _T1>&& __p) _NOEXCEPT
+{
+	return __get_pair<1>::get(_VSTD::move(__p));
+}
+
+#endif
+
 #if _LIBCPP_STD_VER > 11
 
 template<class _Tp, _Tp... _Ip>

libcxx/test/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type.pass.cpp

@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <tuple>
+#include <string>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    typedef std::complex<float> cf;
+    {
+    auto t1 = std::tuple<int, std::string, cf> { 42, "Hi", { 1,2 }};
+    assert ( std::get<int>(t1) == 42 ); // find at the beginning 
+    assert ( std::get<std::string>(t1) == "Hi" ); // find in the middle
+    assert ( std::get<cf>(t1).real() == 1 ); // find at the end
+    assert ( std::get<cf>(t1).imag() == 2 );
+    }
+    
+    {
+    auto t2 = std::tuple<int, std::string, int, cf> { 42, "Hi", 23, { 1,2 }};
+//  get<int> would fail!
+    assert ( std::get<std::string>(t2) == "Hi" );
+    assert (( std::get<cf>(t2) == cf{ 1,2 } ));
+    }
+    
+    {
+    const std::tuple<int, const int, double, double> p5 { 1, 2, 3.4, 5.6 };
+    const int &i1 = std::get<int>(p5);
+    const int &i2 = std::get<const int>(p5);
+    assert ( i1 == 1 );
+    assert ( i2 == 2 );
+    }
+
+    {
+    typedef std::unique_ptr<int> upint;
+    std::tuple<upint> t(upint(new int(4)));
+    upint p = std::get<upint>(std::move(t)); // get rvalue
+    assert(*p == 4);
+    assert(std::get<0>(t) == nullptr); // has been moved from
+    }
+
+#endif
+}

libcxx/test/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type1.fail.cpp

@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <tuple>
+#include <string>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+	typedef std::complex<float> cf;
+	auto t1 = std::make_tuple<int, std::string> ( 42, "Hi" );
+	assert ( std::get<cf>(t1) == cf {1,2} );	// no such type
+#else
+#error
+#endif
+}

libcxx/test/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type2.fail.cpp

@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <tuple>
+#include <string>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+	typedef std::complex<float> cf;
+	auto t1 = std::make_tuple<int, int, std::string, cf> ( 42, 21, "Hi", { 1,2 } );
+	assert ( std::get<int>(t1) == 42 ); // two ints here
+#else
+#error
+#endif
+}

libcxx/test/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type3.fail.cpp

@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <tuple>
+#include <string>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    typedef std::complex<float> cf;
+    auto t1 = std::make_tuple<double, int, std::string, cf, int> ( 42, 21, "Hi", { 1,2 } );
+    assert ( std::get<int>(t1) == 42 ); // two ints here (one at the end)
+#else
+#error
+#endif
+}

libcxx/test/utilities/tuple/tuple.tuple/tuple.elem/tuple.by.type4.fail.cpp

@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <tuple>
+#include <string>
+#include <memory>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+	typedef std::unique_ptr<int> upint;
+	std::tuple<upint> t(upint(new int(4)));
+	upint p = std::get<upint>(t);
+#else
+#error
+#endif
+}

libcxx/test/utilities/utility/pairs/pair.astuple/pairs.by.type.pass.cpp

@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <utility>
+#include <string>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    typedef std::complex<float> cf;
+    {
+    auto t1 = std::make_pair<int, cf> ( 42, { 1,2 } );
+    assert ( std::get<int>(t1) == 42 );
+    assert ( std::get<cf>(t1).real() == 1 );
+    assert ( std::get<cf>(t1).imag() == 2 );
+    }
+    
+    {
+    const std::pair<int, const int> p1 { 1, 2 };
+    const int &i1 = std::get<int>(p1);
+    const int &i2 = std::get<const int>(p1);
+    assert ( i1 == 1 );
+    assert ( i2 == 2 );
+    }
+
+    {
+    typedef std::unique_ptr<int> upint;
+    std::pair<upint, int> t(upint(new int(4)), 42);
+    upint p = std::get<0>(std::move(t)); // get rvalue
+    assert(*p == 4);
+    assert(std::get<0>(t) == nullptr); // has been moved from
+    }
+
+#endif
+}

libcxx/test/utilities/utility/pairs/pair.astuple/pairs.by.type1.fail.cpp

@@ -0,0 +1,24 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <utility>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    typedef std::complex<float> cf;
+    auto t1 = std::make_pair<int, double> ( 42, 3.4 );
+    assert ( std::get<cf>(t1) == cf {1,2} );    // no such type
+#else
+#error
+#endif
+}

libcxx/test/utilities/utility/pairs/pair.astuple/pairs.by.type2.fail.cpp

@@ -0,0 +1,24 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <utility>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    typedef std::complex<float> cf;
+    auto t1 = std::make_pair<int, int> ( 42, 43 );
+    assert ( std::get<int>(t1) == 42 ); // two ints
+#else
+#error
+#endif
+}

libcxx/test/utilities/utility/pairs/pair.astuple/pairs.by.type3.fail.cpp

@@ -0,0 +1,24 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include <utility>
+#include <complex>
+
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+	typedef std::unique_ptr<int> upint;
+	std::pair<upint, int> t(upint(new int(4)), 23);
+	upint p = std::get<upint>(t);
+#else
+#error
+#endif
+}