Implement deduction guides for vector

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@332901 91177308-0d34-0410-b5e6-96231b3b80d8

include/vector

@@ -244,6 +244,10 @@ public:
     bool __invariants() const;
 };
 
+template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+   vector(InputIterator, InputIterator, Allocator = Allocator())
+   -> vector<typename iterator_traits<InputIterator>::value_type, Allocator>;
+
 template <class Allocator> struct hash<std::vector<bool, Allocator>>;
 
 template <class T, class Allocator> bool operator==(const vector<T,Allocator>& x, const vector<T,Allocator>& y);
@@ -316,13 +320,14 @@ template <class _Tp, class _Allocator>
 class __vector_base
     : protected __vector_base_common<true>
 {
-protected:
+public:
-    typedef _Tp                                      value_type;
     typedef _Allocator                               allocator_type;
     typedef allocator_traits<allocator_type>         __alloc_traits;
+    typedef typename __alloc_traits::size_type       size_type;
+protected:
+    typedef _Tp                                      value_type;
     typedef value_type&                              reference;
     typedef const value_type&                        const_reference;
-    typedef typename __alloc_traits::size_type       size_type;
     typedef typename __alloc_traits::difference_type difference_type;
     typedef typename __alloc_traits::pointer         pointer;
     typedef typename __alloc_traits::const_pointer   const_pointer;
@@ -492,8 +497,8 @@ public:
 #if _LIBCPP_STD_VER > 11
     explicit vector(size_type __n, const allocator_type& __a);
 #endif
-    vector(size_type __n, const_reference __x);
+    vector(size_type __n, const value_type& __x);
-    vector(size_type __n, const_reference __x, const allocator_type& __a);
+    vector(size_type __n, const value_type& __x, const allocator_type& __a);
     template <class _InputIterator>
         vector(_InputIterator __first,
                typename enable_if<__is_input_iterator  <_InputIterator>::value &&
@@ -890,6 +895,22 @@ private:
 
 };
 
+#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
+template<class _InputIterator,
+         class _Alloc = typename std::allocator<typename iterator_traits<_InputIterator>::value_type>,
+         class = typename enable_if<__is_allocator<_Alloc>::value, void>::type
+         >
+vector(_InputIterator, _InputIterator)
+  -> vector<typename iterator_traits<_InputIterator>::value_type, _Alloc>;
+
+template<class _InputIterator,
+         class _Alloc,
+         class = typename enable_if<__is_allocator<_Alloc>::value, void>::type
+         >
+vector(_InputIterator, _InputIterator, _Alloc)
+  -> vector<typename iterator_traits<_InputIterator>::value_type, _Alloc>;
+#endif
+
 template <class _Tp, class _Allocator>
 void
 vector<_Tp, _Allocator>::__swap_out_circular_buffer(__split_buffer<value_type, allocator_type&>& __v)
@@ -1099,7 +1120,7 @@ vector<_Tp, _Allocator>::vector(size_type __n, const allocator_type& __a)
 #endif
 
 template <class _Tp, class _Allocator>
-vector<_Tp, _Allocator>::vector(size_type __n, const_reference __x)
+vector<_Tp, _Allocator>::vector(size_type __n, const value_type& __x)
 {
 #if _LIBCPP_DEBUG_LEVEL >= 2
     __get_db()->__insert_c(this);
@@ -1112,7 +1133,7 @@ vector<_Tp, _Allocator>::vector(size_type __n, const_reference __x)
 }
 
 template <class _Tp, class _Allocator>
-vector<_Tp, _Allocator>::vector(size_type __n, const_reference __x, const allocator_type& __a)
+vector<_Tp, _Allocator>::vector(size_type __n, const value_type& __x, const allocator_type& __a)
     : __base(__a)
 {
 #if _LIBCPP_DEBUG_LEVEL >= 2

test/std/containers/sequences/vector/vector.cons/deduct.fail.cpp

@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <vector>
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// UNSUPPORTED: libcpp-no-deduction-guides
+
+
+// template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+//    vector(InputIterator, InputIterator, Allocator = Allocator())
+//    -> vector<typename iterator_traits<InputIterator>::value_type, Allocator>;
+//
+
+
+#include <deque>
+#include <iterator>
+#include <cassert>
+#include <cstddef>
+
+
+int main()
+{  
+//  Test the explicit deduction guides
+
+//  Test the implicit deduction guides
+    {
+//  vector (allocator &)
+    std::vector vec((std::allocator<int>()));  // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'vector'}}
+//  Note: The extra parens are necessary, since otherwise clang decides it is a function declaration.
+//  Also, we can't use {} instead of parens, because that constructs a
+//      deque<allocator<int>, allocator<allocator<int>>>
+    }
+
+}

test/std/containers/sequences/vector/vector.cons/deduct.pass.cpp

@@ -0,0 +1,116 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <vector>
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// UNSUPPORTED: libcpp-no-deduction-guides
+
+
+// template <class InputIterator, class Allocator = allocator<typename iterator_traits<InputIterator>::value_type>>
+//    deque(InputIterator, InputIterator, Allocator = Allocator())
+//    -> deque<typename iterator_traits<InputIterator>::value_type, Allocator>;
+//
+
+
+#include <vector>
+#include <iterator>
+#include <cassert>
+#include <cstddef>
+#include <climits> // INT_MAX
+
+#include "test_macros.h"
+#include "test_iterators.h"
+#include "test_allocator.h"
+
+struct A {};
+
+int main()
+{
+  
+//  Test the explicit deduction guides
+    {
+    const int arr[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
+    std::vector vec(std::begin(arr), std::end(arr));
+
+    static_assert(std::is_same_v<decltype(vec), std::vector<int>>, "");
+    assert(std::equal(vec.begin(), vec.end(), std::begin(arr), std::end(arr)));
+    }
+
+    {
+    const long arr[] = {INT_MAX, 1L, 2L, 3L };
+    std::vector vec(std::begin(arr), std::end(arr), std::allocator<long>());
+    static_assert(std::is_same_v<decltype(vec)::value_type, long>, "");
+    assert(vec.size() == 4);
+    assert(vec[0] == INT_MAX);
+    assert(vec[1] == 1L);
+    assert(vec[2] == 2L);
+    }
+    
+//  Test the implicit deduction guides
+
+    {
+//  We don't expect this one to work.
+//  std::vector vec(std::allocator<int>()); // vector (allocator &)
+    }
+
+    {
+    std::vector vec(1, A{}); // vector (size_type, T)
+    static_assert(std::is_same_v<decltype(vec)::value_type, A>, "");
+    static_assert(std::is_same_v<decltype(vec)::allocator_type, std::allocator<A>>, "");
+    assert(vec.size() == 1);
+    }
+
+    {
+    std::vector vec(1, A{}, test_allocator<A>()); // vector (size_type, T, allocator)
+    static_assert(std::is_same_v<decltype(vec)::value_type, A>, "");
+    static_assert(std::is_same_v<decltype(vec)::allocator_type, test_allocator<A>>, "");
+    assert(vec.size() == 1);
+    }
+
+    {
+    std::vector vec{1U, 2U, 3U, 4U, 5U}; // vector(initializer-list)
+    static_assert(std::is_same_v<decltype(vec)::value_type, unsigned>, "");
+    assert(vec.size() == 5);
+    assert(vec[2] == 3U);
+    }
+
+    {
+    std::vector vec({1.0, 2.0, 3.0, 4.0}, test_allocator<double>()); // vector(initializer-list, allocator)
+    static_assert(std::is_same_v<decltype(vec)::value_type, double>, "");
+    static_assert(std::is_same_v<decltype(vec)::allocator_type, test_allocator<double>>, "");
+    assert(vec.size() == 4);
+    assert(vec[3] == 4.0);
+    }
+
+    {
+    std::vector<long double> source;
+    std::vector vec(source); // vector(vector &)
+    static_assert(std::is_same_v<decltype(vec)::value_type, long double>, "");
+    static_assert(std::is_same_v<decltype(vec)::allocator_type, std::allocator<long double>>, "");
+    assert(vec.size() == 0);
+    }
+
+
+//  A couple of vector<bool> tests, too!
+    {
+    std::vector vec(3, true); // vector(initializer-list)
+    static_assert(std::is_same_v<decltype(vec)::value_type, bool>, "");
+    static_assert(std::is_same_v<decltype(vec)::allocator_type, std::allocator<bool>>, "");
+    assert(vec.size() == 3);
+    assert(vec[0] && vec[1] && vec[2]);
+    }
+
+    {
+    std::vector<bool> source;
+    std::vector vec(source); // vector(vector &)
+    static_assert(std::is_same_v<decltype(vec)::value_type, bool>, "");
+    static_assert(std::is_same_v<decltype(vec)::allocator_type, std::allocator<bool>>, "");
+    assert(vec.size() == 0);
+    }
+}