libcxx/test/std/containers/associative/multiset/multiset.cons/deduct.verify.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // UNSUPPORTED: c++03, c++11, c++14
  10
  11 // <set>
  12
  13 // template<class InputIterator,
  14 //          class Compare = less<iter-value-type<InputIterator>>,
  15 //          class Allocator = allocator<iter-value-type<InputIterator>>>
  16 // multiset(InputIterator, InputIterator,
  17 //          Compare = Compare(), Allocator = Allocator())
  18 //   -> multiset<iter-value-type<InputIterator>, Compare, Allocator>;
  19 // template<class Key, class Compare = less<Key>,
  20 //          class Allocator = allocator<Key>>
  21 // multiset(initializer_list<Key>, Compare = Compare(), Allocator = Allocator())
  22 //   -> multiset<Key, Compare, Allocator>;
  23 // template<class InputIterator, class Allocator>
  24 // multiset(InputIterator, InputIterator, Allocator)
  25 //   -> multiset<iter-value-type<InputIterator>,
  26 //               less<iter-value-type<InputIterator>>, Allocator>;
  27 // template<class Key, class Allocator>
  28 // multiset(initializer_list<Key>, Allocator)
  29 //   -> multiset<Key, less<Key>, Allocator>;
  30
  31 #include <functional>
  32 #include <set>
  33 #include <type_traits>
  34
  35 struct NotAnAllocator {
  36   friend bool operator<(NotAnAllocator, NotAnAllocator) { return false; }
  37 };
  38
  39 int main(int, char **) {
  40   {
  41     // cannot deduce Key from nothing
  42     std::multiset s;
  43     // expected-error-re@-1{{no viable constructor or deduction guide for deduction of template arguments of '{{(std::)?}}multiset'}}
  44   }
  45   {
  46     // cannot deduce Key from just (Compare)
  47     std::multiset s(std::less<int>{});
  48     // expected-error-re@-1{{no viable constructor or deduction guide for deduction of template arguments of '{{(std::)?}}multiset'}}
  49   }
  50   {
  51     // cannot deduce Key from just (Compare, Allocator)
  52     std::multiset s(std::less<int>{}, std::allocator<int>{});
  53     // expected-error-re@-1{{no viable constructor or deduction guide for deduction of template arguments of '{{(std::)?}}multiset'}}
  54   }
  55   {
  56     // cannot deduce Key from multiset(Allocator)
  57     std::multiset s(std::allocator<int>{});
  58     // expected-error-re@-1{{no viable constructor or deduction guide for deduction of template arguments of '{{(std::)?}}multiset'}}
  59   }
  60   {
  61     // since we have parens, not braces, this deliberately does not find the
  62     // initializer_list constructor
  63     NotAnAllocator a;
  64     std::multiset s(a);
  65     // expected-error-re@-1{{no viable constructor or deduction guide for deduction of template arguments of '{{(std::)?}}multiset'}}
  66   }
  67
  68   return 0;
  69 }