xref: /llvm-project/libcxx/test/std/containers/views/views.span/span.cons/initializer_list.verify.cpp (revision dbbeee6b8357c5a68543f612f3b2b607f1911b4c)
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, c++17
10 
11 // <span>
12 
13 // constexpr explicit(extent != dynamic_extent) span(std::initializer_list<value_type> il); // Since C++26
14 
15 #include <span>
16 #include <utility>
17 
18 #include "test_macros.h"
19 
20 // Test P2447R4 "Annex C examples"
21 
22 void one(std::pair<int, int>);
23 void one(std::span<const int>);
24 
25 void two(std::span<const int, 2>);
26 
test_P2447R4_annex_c_examples()27 void test_P2447R4_annex_c_examples() {
28   // 1. Overload resolution is affected
29 #if TEST_STD_VER >= 26
30   // expected-error@+1 {{call to 'one' is ambiguous}}
31   one({1, 2});
32 #else
33   // expected-no-diagnostics
34   one({1, 2});
35 #endif
36 
37 // 2. The `initializer_list` ctor has high precedence
38 #if TEST_STD_VER >= 26
39   // expected-error@+1 {{chosen constructor is explicit in copy-initialization}}
40   two({{1, 2}});
41 #else
42   // expected-no-diagnostics
43   two({{1, 2}});
44 #endif
45 
46   // 3. Implicit two-argument construction with a highly convertible value_type
47   // --> tested in "initializer_list.pass.cpp"
48 }
49