Deduction guides for the container adaptors - queue, stack, and priority_queue

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@332927 91177308-0d34-0410-b5e6-96231b3b80d8

include/queue

@@ -69,6 +69,12 @@ public:
     void swap(queue& q) noexcept(is_nothrow_swappable_v<Container>)
 };
 
+template<class Container>
+  queue(Container) -> queue<typename Container::value_type, Container>; // C++17
+  
+template<class Container, class Allocator> 
+  queue(Container, Allocator) -> queue<typename Container::value_type, Container>; // C++17
+
 template <class T, class Container>
   bool operator==(const queue<T, Container>& x,const queue<T, Container>& y);
 
@@ -157,6 +163,20 @@ public:
                  is_nothrow_swappable_v<Comp>)
 };
 
+template <class Compare, class Container>
+priority_queue(Compare, Container)
+    -> priority_queue<typename Container::value_type, Container, Compare>; // C++17
+  
+template<class InputIterator, 
+         class Compare = less<typename iterator_traits<InputIterator>::value_type>,
+         class Container = vector<typename iterator_traits<InputIterator>::value_type>>
+priority_queue(InputIterator, InputIterator, Compare = Compare(), Container = Container())
+    -> priority_queue<typename iterator_traits<InputIterator>::value_type, Container, Compare>; // C++17
+  
+template<class Compare, class Container, class Allocator>
+priority_queue(Compare, Container, Allocator)
+    -> priority_queue<typename Container::value_type, Container, Compare>; // C++17
+
 template <class T, class Container, class Compare>
   void swap(priority_queue<T, Container, Compare>& x,
             priority_queue<T, Container, Compare>& y)
@@ -321,6 +341,22 @@ public:
     operator< (const queue<_T1, _C1>& __x,const queue<_T1, _C1>& __y);
 };
 
+#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
+template<class _Container,
+         class = typename enable_if<!__is_allocator<_Container>::value, nullptr_t>::type
+>
+queue(_Container)
+    -> queue<typename _Container::value_type, _Container>;
+  
+template<class _Container,
+         class _Alloc,
+         class = typename enable_if<!__is_allocator<_Container>::value, nullptr_t>::type,
+         class = typename enable_if< __is_allocator<_Alloc>::value, nullptr_t>::type
+>
+queue(_Container, _Alloc)
+    -> queue<typename _Container::value_type, _Container>;
+#endif
+
 template <class _Tp, class _Container>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
@@ -515,6 +551,36 @@ public:
                    __is_nothrow_swappable<value_compare>::value);
 };
 
+#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
+template <class _Compare,
+          class _Container,
+          class = typename enable_if<!__is_allocator<_Compare>::value, nullptr_t>::type,
+          class = typename enable_if<!__is_allocator<_Container>::value, nullptr_t>::type
+>
+priority_queue(_Compare, _Container)
+    -> priority_queue<typename _Container::value_type, _Container, _Compare>;
+  
+template<class _InputIterator, 
+         class _Compare   = less<typename iterator_traits<_InputIterator>::value_type>,
+         class _Container = vector<typename iterator_traits<_InputIterator>::value_type>,
+         class = typename enable_if< __is_input_iterator<_InputIterator>::value, nullptr_t>::type,
+         class = typename enable_if<!__is_allocator<_Compare>::value, nullptr_t>::type,
+         class = typename enable_if<!__is_allocator<_Container>::value, nullptr_t>::type
+>
+priority_queue(_InputIterator, _InputIterator, _Compare = _Compare(), _Container = _Container())
+    -> priority_queue<typename iterator_traits<_InputIterator>::value_type, _Container, _Compare>;
+  
+template<class _Compare, 
+         class _Container,
+         class _Alloc,
+         class = typename enable_if<!__is_allocator<_Compare>::value, nullptr_t>::type,
+         class = typename enable_if<!__is_allocator<_Container>::value, nullptr_t>::type,
+         class = typename enable_if< __is_allocator<_Alloc>::value, nullptr_t>::type
+>
+priority_queue(_Compare, _Container, _Alloc)
+    -> priority_queue<typename _Container::value_type, _Container, _Compare>;
+#endif
+
 template <class _Tp, class _Container, class _Compare>
 inline
 priority_queue<_Tp, _Container, _Compare>::priority_queue(const _Compare& __comp,

include/stack

@@ -61,6 +61,12 @@ public:
     void swap(stack& c) noexcept(is_nothrow_swappable_v<Container>)
 };
 
+template<class Container>
+  stack(Container) -> stack<typename Container::value_type, Container>;  // C++17
+  
+template<class Container, class Allocator> 
+  stack(Container, Allocator) -> stack<typename Container::value_type, Container>; // C++17
+
 template <class T, class Container>
   bool operator==(const stack<T, Container>& x, const stack<T, Container>& y);
 template <class T, class Container>
@@ -229,6 +235,22 @@ public:
     operator< (const stack<T1, _C1>& __x, const stack<T1, _C1>& __y);
 };
 
+#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
+template<class _Container,
+         class = typename enable_if<!__is_allocator<_Container>::value, nullptr_t>::type
+>
+stack(_Container)
+    -> stack<typename _Container::value_type, _Container>;
+  
+template<class _Container,
+         class _Alloc,
+         class = typename enable_if<!__is_allocator<_Container>::value, nullptr_t>::type,
+         class = typename enable_if< __is_allocator<_Alloc>::value, nullptr_t>::type
+         > 
+stack(_Container, _Alloc)
+    -> stack<typename _Container::value_type, _Container>;
+#endif
+
 template <class _Tp, class _Container>
 inline _LIBCPP_INLINE_VISIBILITY
 bool

test/std/containers/container.adaptors/queue/queue.cons/deduct.fail.cpp

@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <queue>
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// UNSUPPORTED: libcpp-no-deduction-guides
+
+#include <queue>
+#include <list>
+#include <iterator>
+#include <cassert>
+#include <cstddef>
+
+
+int main()
+{  
+//  Test the explicit deduction guides
+    {
+//  queue(const Container&, const Alloc&);
+//  The '45' is not an allocator
+    std::queue que(std::list<int>{1,2,3}, 45);  // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'queue'}}
+    }
+
+    {
+//  queue(const queue&, const Alloc&);
+//  The '45' is not an allocator
+    std::queue<int> source;
+    std::queue que(source, 45);  // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'queue'}}
+    }
+
+//  Test the implicit deduction guides
+    {
+//  queue (allocator &)
+    std::queue que((std::allocator<int>()));  // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'queue'}}
+//  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
+//      stack<allocator<int>, allocator<allocator<int>>>
+    }
+
+}

test/std/containers/container.adaptors/queue/queue.cons/deduct.pass.cpp

@@ -0,0 +1,89 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <queue>
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// UNSUPPORTED: libcpp-no-deduction-guides
+
+
+// template<class Container>
+//   queue(Container) -> queue<typename Container::value_type, Container>;
+//   
+// template<class Container, class Allocator> 
+//   queue(Container, Allocator) -> queue<typename Container::value_type, Container>;
+
+
+#include <queue>
+#include <list>
+#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
+    {
+    std::list<int> l{0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
+    std::queue que(l);
+
+    static_assert(std::is_same_v<decltype(que), std::queue<int, std::list<int>>>, "");
+    assert(que.size() == l.size());
+    assert(que.back() == l.back());
+    }
+
+    {
+    std::list<long, test_allocator<long>> l{10, 11, 12, 13, 14, 15, 16, 17, 18, 19 };
+    std::queue que(l, test_allocator<long>(0,2)); // different allocator
+    static_assert(std::is_same_v<decltype(que)::container_type, std::list<long, test_allocator<long>>>, "");
+    static_assert(std::is_same_v<decltype(que)::value_type, long>, "");
+    assert(que.size() == 10);
+    assert(que.back() == 19);
+//  I'd like to assert that we've gotten the right allocator in the queue, but
+//  I don't know how to get at the underlying container.
+    }
+    
+//  Test the implicit deduction guides
+    {
+//  We don't expect this one to work - no way to implicitly get value_type
+//  std::queue que(std::allocator<int>()); // queue (allocator &)
+    }
+
+    {
+    std::queue<A> source;
+    std::queue que(source); // queue(queue &)
+    static_assert(std::is_same_v<decltype(que)::value_type, A>, "");
+    static_assert(std::is_same_v<decltype(que)::container_type, std::deque<A>>, "");
+    assert(que.size() == 0);
+    }
+
+    {
+//  This one is odd - you can pass an allocator in to use, but the allocator
+//  has to match the type of the one used by the underlying container
+    typedef short T;
+    typedef test_allocator<T> A;
+    typedef std::deque<T, A> C;
+
+    C c{0,1,2,3};
+    std::queue<T, C> source(c);
+    std::queue que(source, A(2)); // queue(queue &, allocator)
+    static_assert(std::is_same_v<decltype(que)::value_type, T>, "");
+    static_assert(std::is_same_v<decltype(que)::container_type, C>, "");
+    assert(que.size() == 4);
+    assert(que.back() == 3);
+    }
+
+}

test/std/containers/container.adaptors/stack/stack.cons/deduct.fail.cpp

@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <stack>
+// 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 <stack>
+#include <list>
+#include <iterator>
+#include <cassert>
+#include <cstddef>
+
+
+int main()
+{  
+//  Test the explicit deduction guides
+    {
+//  stack(const Container&, const Alloc&);
+//  The '45' is not an allocator
+    std::stack stk(std::list<int>({1,2,3}), 45);  // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'stack'}}
+    }
+
+    {
+//  stack(const stack&, const Alloc&);
+//  The '45' is not an allocator
+    std::stack<int> source;
+    std::stack stk(source, 45);  // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'stack'}}
+    }
+
+//  Test the implicit deduction guides
+    {
+//  stack (allocator &)
+    std::stack stk((std::allocator<int>()));  // expected-error {{no viable constructor or deduction guide for deduction of template arguments of 'stack'}}
+//  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
+//      stack<allocator<int>, allocator<allocator<int>>>
+    }
+
+}

test/std/containers/container.adaptors/stack/stack.cons/deduct.pass.cpp

@@ -0,0 +1,91 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <stack>
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// UNSUPPORTED: libcpp-no-deduction-guides
+
+
+// template<class Container>
+//   stack(Container) -> stack<typename Container::value_type, Container>;
+//   
+// template<class Container, class Allocator> 
+//   stack(Container, Allocator) -> stack<typename Container::value_type, Container>;
+
+
+#include <stack>
+#include <vector>
+#include <list>
+#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
+    {
+    std::vector<int> v{0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
+    std::stack stk(v);
+
+    static_assert(std::is_same_v<decltype(stk), std::stack<int, std::vector<int>>>, "");
+    assert(stk.size() == v.size());
+    assert(stk.top() == v.back());
+    }
+
+    {
+    std::list<long, test_allocator<long>> l{10, 11, 12, 13, 14, 15, 16, 17, 18, 19 };
+    std::stack stk(l, test_allocator<long>(0,2)); // different allocator
+    static_assert(std::is_same_v<decltype(stk)::container_type, std::list<long, test_allocator<long>>>, "");
+    static_assert(std::is_same_v<decltype(stk)::value_type, long>, "");
+    assert(stk.size() == 10);
+    assert(stk.top() == 19);
+//  I'd like to assert that we've gotten the right allocator in the stack, but
+//  I don't know how to get at the underlying container.
+    }
+    
+//  Test the implicit deduction guides
+
+    {
+//  We don't expect this one to work - no way to implicitly get value_type
+//  std::stack stk(std::allocator<int>()); // stack (allocator &)
+    }
+
+    {
+    std::stack<A> source;
+    std::stack stk(source); // stack(stack &)
+    static_assert(std::is_same_v<decltype(stk)::value_type, A>, "");
+    static_assert(std::is_same_v<decltype(stk)::container_type, std::deque<A>>, "");
+    assert(stk.size() == 0);
+    }
+
+    {
+//  This one is odd - you can pass an allocator in to use, but the allocator
+//  has to match the type of the one used by the underlying container
+    typedef short T;
+    typedef test_allocator<T> A;
+    typedef std::deque<T, A> C;
+
+    C c{0,1,2,3};
+    std::stack<T, C> source(c);
+    std::stack stk(source, A(2)); // stack(stack &, allocator)
+    static_assert(std::is_same_v<decltype(stk)::value_type, T>, "");
+    static_assert(std::is_same_v<decltype(stk)::container_type, C>, "");
+    assert(stk.size() == 4);
+    assert(stk.top() == 3);
+    }
+
+}