libcxx/test/std/containers/unord/unord.set/unord.set.cnstr/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 // <unordered_set>
  12
  13 // template<class InputIterator,
  14 //        class Hash = hash<iter-value-type<InputIterator>>,
  15 //        class Pred = equal_to<iter-value-type<InputIterator>>,
  16 //        class Allocator = allocator<iter-value-type<InputIterator>>>
  17 // unordered_set(InputIterator, InputIterator, typename see below::size_type = see below,
  18 //               Hash = Hash(), Pred = Pred(), Allocator = Allocator())
  19 //   -> unordered_set<iter-value-type<InputIterator>,
  20 //                    Hash, Pred, Allocator>;
  21 //
  22 // template<class T, class Hash = hash<T>,
  23 //        class Pred = equal_to<T>, class Allocator = allocator<T>>
  24 // unordered_set(initializer_list<T>, typename see below::size_type = see below,
  25 //               Hash = Hash(), Pred = Pred(), Allocator = Allocator())
  26 //   -> unordered_set<T, Hash, Pred, Allocator>;
  27 //
  28 // template<class InputIterator, class Allocator>
  29 // unordered_set(InputIterator, InputIterator, typename see below::size_type, Allocator)
  30 //   -> unordered_set<iter-value-type<InputIterator>,
  31 //                    hash<iter-value-type<InputIterator>>,
  32 //                    equal_to<iter-value-type<InputIterator>>,
  33 //                    Allocator>;
  34 //
  35 // template<class InputIterator, class Hash, class Allocator>
  36 // unordered_set(InputIterator, InputIterator, typename see below::size_type,
  37 //               Hash, Allocator)
  38 //   -> unordered_set<iter-value-type<InputIterator>, Hash,
  39 //                    equal_to<iter-value-type<InputIterator>>,
  40 //                    Allocator>;
  41 //
  42 // template<class T, class Allocator>
  43 // unordered_set(initializer_list<T>, typename see below::size_type, Allocator)
  44 //   -> unordered_set<T, hash<T>, equal_to<T>, Allocator>;
  45 //
  46 // template<class T, class Hash, class Allocator>
  47 // unordered_set(initializer_list<T>, typename see below::size_type, Hash, Allocator)
  48 //   -> unordered_set<T, Hash, equal_to<T>, Allocator>;
  49
  50 #include <functional>
  51 #include <unordered_set>
  52
  53 int main(int, char**)
  54 {
  55     {
  56         // cannot deduce Key from nothing
  57         std::unordered_set s;
  58             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  59     }
  60     {
  61         // cannot deduce Key from just (Size)
  62         std::unordered_set s(42);
  63             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  64     }
  65     {
  66         // cannot deduce Key from just (Size, Hash)
  67         std::unordered_set s(42, std::hash<int>());
  68             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  69     }
  70     {
  71         // cannot deduce Key from just (Size, Hash, Pred)
  72         std::unordered_set s(42, std::hash<int>(), std::equal_to<>());
  73             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  74     }
  75     {
  76         // cannot deduce Key from just (Size, Hash, Pred, Allocator)
  77         std::unordered_set s(42, std::hash<int>(), std::equal_to<>(), std::allocator<int>());
  78             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  79     }
  80     {
  81         // cannot deduce Key from just (Allocator)
  82         std::unordered_set s(std::allocator<int>{});
  83             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  84     }
  85     {
  86         // cannot deduce Key from just (Size, Allocator)
  87         std::unordered_set s(42, std::allocator<int>());
  88             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  89     }
  90     {
  91         // cannot deduce Key from just (Size, Hash, Allocator)
  92         std::unordered_set s(42, std::hash<short>(), std::allocator<int>());
  93             // expected-error@-1{{no viable constructor or deduction guide for deduction of template arguments of 'unordered_set'}}
  94     }
  95
  96     return 0;
  97 }