blob: 55a08508296d90d158ce2d086de1dd052517725f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
// Copyright 2022 The Abseil Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_STRINGS_INTERNAL_HAS_ABSL_STRINGIFY_H_
#define ABSL_STRINGS_INTERNAL_HAS_ABSL_STRINGIFY_H_
#include <string>
#include <type_traits>
#include <utility>
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace strings_internal {
// This is an empty class not intended to be used. It exists so that
// `HasAbslStringify` can reference a universal class rather than needing to be
// copied for each new sink.
class UnimplementedSink {
public:
void Append(size_t count, char ch);
void Append(string_view v);
// Support `absl::Format(&sink, format, args...)`.
friend void AbslFormatFlush(UnimplementedSink* sink, absl::string_view v);
};
template <typename T, typename = void>
struct HasAbslStringify : std::false_type {};
template <typename T>
struct HasAbslStringify<
T, std::enable_if_t<std::is_void<decltype(AbslStringify(
std::declval<strings_internal::UnimplementedSink&>(),
std::declval<const T&>()))>::value>> : std::true_type {};
} // namespace strings_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_STRINGS_INTERNAL_HAS_ABSL_STRINGIFY_H_
|
