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// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/types/supports_ostream_operator.h"
#include <stdint.h>
#include <ostream>
#include <string>
namespace base {
namespace {
enum SimpleEnum { SIMPLE_ENUM };
enum EnumWithExplicitType : uint64_t { ENUM_WITH_EXPLICIT_TYPE };
enum class ScopedEnum { SCOPED_ENUM };
enum class ScopedEnumWithOperator { SCOPED_ENUM_WITH_OPERATOR };
std::ostream& operator<<(std::ostream& os, ScopedEnumWithOperator v) {
return os;
}
struct SimpleStruct {};
struct StructWithOperator {};
std::ostream& operator<<(std::ostream& os, const StructWithOperator& v) {
return os;
}
// A few standard types that definitely support printing.
static_assert(internal::SupportsOstreamOperator<int>::value,
"ints should be printable");
static_assert(internal::SupportsOstreamOperator<const char*>::value,
"C strings should be printable");
static_assert(internal::SupportsOstreamOperator<std::string>::value,
"std::string should be printable");
// Various kinds of enums operator<< support.
static_assert(internal::SupportsOstreamOperator<SimpleEnum>::value,
"simple enum should be printable by value");
static_assert(internal::SupportsOstreamOperator<const SimpleEnum&>::value,
"simple enum should be printable by const ref");
static_assert(internal::SupportsOstreamOperator<EnumWithExplicitType>::value,
"enum with explicit type should be printable by value");
static_assert(
internal::SupportsOstreamOperator<const EnumWithExplicitType&>::value,
"enum with explicit type should be printable by const ref");
static_assert(!internal::SupportsOstreamOperator<ScopedEnum>::value,
"scoped enum should not be printable by value");
static_assert(!internal::SupportsOstreamOperator<const ScopedEnum&>::value,
"simple enum should not be printable by const ref");
static_assert(internal::SupportsOstreamOperator<ScopedEnumWithOperator>::value,
"scoped enum with operator<< should be printable by value");
static_assert(
internal::SupportsOstreamOperator<const ScopedEnumWithOperator&>::value,
"scoped enum with operator<< should be printable by const ref");
// operator<< support on structs.
static_assert(!internal::SupportsOstreamOperator<SimpleStruct>::value,
"simple struct should not be printable by value");
static_assert(!internal::SupportsOstreamOperator<const SimpleStruct&>::value,
"simple struct should not be printable by const ref");
static_assert(internal::SupportsOstreamOperator<StructWithOperator>::value,
"struct with operator<< should be printable by value");
static_assert(
internal::SupportsOstreamOperator<const StructWithOperator&>::value,
"struct with operator<< should be printable by const ref");
} // namespace
} // namespace base
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