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Diffstat (limited to 'third_party/abseil_cpp/absl/flags/marshalling.h')
| -rw-r--r-- | third_party/abseil_cpp/absl/flags/marshalling.h | 264 |
1 files changed, 0 insertions, 264 deletions
diff --git a/third_party/abseil_cpp/absl/flags/marshalling.h b/third_party/abseil_cpp/absl/flags/marshalling.h deleted file mode 100644 index 0b5033547e..0000000000 --- a/third_party/abseil_cpp/absl/flags/marshalling.h +++ /dev/null @@ -1,264 +0,0 @@ -// -// Copyright 2019 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. -// -// ----------------------------------------------------------------------------- -// File: marshalling.h -// ----------------------------------------------------------------------------- -// -// This header file defines the API for extending Abseil flag support to -// custom types, and defines the set of overloads for fundamental types. -// -// Out of the box, the Abseil flags library supports the following types: -// -// * `bool` -// * `int16_t` -// * `uint16_t` -// * `int32_t` -// * `uint32_t` -// * `int64_t` -// * `uint64_t` -// * `float` -// * `double` -// * `std::string` -// * `std::vector<std::string>` -// * `absl::LogSeverity` (provided natively for layering reasons) -// -// Note that support for integral types is implemented using overloads for -// variable-width fundamental types (`short`, `int`, `long`, etc.). However, -// you should prefer the fixed-width integral types (`int32_t`, `uint64_t`, -// etc.) we've noted above within flag definitions. -// -// In addition, several Abseil libraries provide their own custom support for -// Abseil flags. Documentation for these formats is provided in the type's -// `AbslParseFlag()` definition. -// -// The Abseil time library provides the following support for civil time values: -// -// * `absl::CivilSecond` -// * `absl::CivilMinute` -// * `absl::CivilHour` -// * `absl::CivilDay` -// * `absl::CivilMonth` -// * `absl::CivilYear` -// -// and also provides support for the following absolute time values: -// -// * `absl::Duration` -// * `absl::Time` -// -// Additional support for Abseil types will be noted here as it is added. -// -// You can also provide your own custom flags by adding overloads for -// `AbslParseFlag()` and `AbslUnparseFlag()` to your type definitions. (See -// below.) -// -// ----------------------------------------------------------------------------- -// Adding Type Support for Abseil Flags -// ----------------------------------------------------------------------------- -// -// To add support for your user-defined type, add overloads of `AbslParseFlag()` -// and `AbslUnparseFlag()` as free (non-member) functions to your type. If `T` -// is a class type, these functions can be friend function definitions. These -// overloads must be added to the same namespace where the type is defined, so -// that they can be discovered by Argument-Dependent Lookup (ADL). -// -// Example: -// -// namespace foo { -// -// enum OutputMode { kPlainText, kHtml }; -// -// // AbslParseFlag converts from a string to OutputMode. -// // Must be in same namespace as OutputMode. -// -// // Parses an OutputMode from the command line flag value `text. Returns -// // `true` and sets `*mode` on success; returns `false` and sets `*error` -// // on failure. -// bool AbslParseFlag(absl::string_view text, -// OutputMode* mode, -// std::string* error) { -// if (text == "plaintext") { -// *mode = kPlainText; -// return true; -// } -// if (text == "html") { -// *mode = kHtml; -// return true; -// } -// *error = "unknown value for enumeration"; -// return false; -// } -// -// // AbslUnparseFlag converts from an OutputMode to a string. -// // Must be in same namespace as OutputMode. -// -// // Returns a textual flag value corresponding to the OutputMode `mode`. -// std::string AbslUnparseFlag(OutputMode mode) { -// switch (mode) { -// case kPlainText: return "plaintext"; -// case kHtml: return "html"; -// } -// return absl::StrCat(mode); -// } -// -// Notice that neither `AbslParseFlag()` nor `AbslUnparseFlag()` are class -// members, but free functions. `AbslParseFlag/AbslUnparseFlag()` overloads -// for a type should only be declared in the same file and namespace as said -// type. The proper `AbslParseFlag/AbslUnparseFlag()` implementations for a -// given type will be discovered via Argument-Dependent Lookup (ADL). -// -// `AbslParseFlag()` may need, in turn, to parse simpler constituent types -// using `absl::ParseFlag()`. For example, a custom struct `MyFlagType` -// consisting of a `std::pair<int, std::string>` would add an `AbslParseFlag()` -// overload for its `MyFlagType` like so: -// -// Example: -// -// namespace my_flag_type { -// -// struct MyFlagType { -// std::pair<int, std::string> my_flag_data; -// }; -// -// bool AbslParseFlag(absl::string_view text, MyFlagType* flag, -// std::string* err); -// -// std::string AbslUnparseFlag(const MyFlagType&); -// -// // Within the implementation, `AbslParseFlag()` will, in turn invoke -// // `absl::ParseFlag()` on its constituent `int` and `std::string` types -// // (which have built-in Abseil flag support. -// -// bool AbslParseFlag(absl::string_view text, MyFlagType* flag, -// std::string* err) { -// std::pair<absl::string_view, absl::string_view> tokens = -// absl::StrSplit(text, ','); -// if (!absl::ParseFlag(tokens.first, &flag->my_flag_data.first, err)) -// return false; -// if (!absl::ParseFlag(tokens.second, &flag->my_flag_data.second, err)) -// return false; -// return true; -// } -// -// // Similarly, for unparsing, we can simply invoke `absl::UnparseFlag()` on -// // the constituent types. -// std::string AbslUnparseFlag(const MyFlagType& flag) { -// return absl::StrCat(absl::UnparseFlag(flag.my_flag_data.first), -// ",", -// absl::UnparseFlag(flag.my_flag_data.second)); -// } -#ifndef ABSL_FLAGS_MARSHALLING_H_ -#define ABSL_FLAGS_MARSHALLING_H_ - -#include <string> -#include <vector> - -#include "absl/base/config.h" -#include "absl/strings/string_view.h" - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace flags_internal { - -// Overloads of `AbslParseFlag()` and `AbslUnparseFlag()` for fundamental types. -bool AbslParseFlag(absl::string_view, bool*, std::string*); -bool AbslParseFlag(absl::string_view, short*, std::string*); // NOLINT -bool AbslParseFlag(absl::string_view, unsigned short*, std::string*); // NOLINT -bool AbslParseFlag(absl::string_view, int*, std::string*); // NOLINT -bool AbslParseFlag(absl::string_view, unsigned int*, std::string*); // NOLINT -bool AbslParseFlag(absl::string_view, long*, std::string*); // NOLINT -bool AbslParseFlag(absl::string_view, unsigned long*, std::string*); // NOLINT -bool AbslParseFlag(absl::string_view, long long*, std::string*); // NOLINT -bool AbslParseFlag(absl::string_view, unsigned long long*, // NOLINT - std::string*); -bool AbslParseFlag(absl::string_view, float*, std::string*); -bool AbslParseFlag(absl::string_view, double*, std::string*); -bool AbslParseFlag(absl::string_view, std::string*, std::string*); -bool AbslParseFlag(absl::string_view, std::vector<std::string>*, std::string*); - -template <typename T> -bool InvokeParseFlag(absl::string_view input, T* dst, std::string* err) { - // Comment on next line provides a good compiler error message if T - // does not have AbslParseFlag(absl::string_view, T*, std::string*). - return AbslParseFlag(input, dst, err); // Is T missing AbslParseFlag? -} - -// Strings and std:: containers do not have the same overload resolution -// considerations as fundamental types. Naming these 'AbslUnparseFlag' means we -// can avoid the need for additional specializations of Unparse (below). -std::string AbslUnparseFlag(absl::string_view v); -std::string AbslUnparseFlag(const std::vector<std::string>&); - -template <typename T> -std::string Unparse(const T& v) { - // Comment on next line provides a good compiler error message if T does not - // have UnparseFlag. - return AbslUnparseFlag(v); // Is T missing AbslUnparseFlag? -} - -// Overloads for builtin types. -std::string Unparse(bool v); -std::string Unparse(short v); // NOLINT -std::string Unparse(unsigned short v); // NOLINT -std::string Unparse(int v); // NOLINT -std::string Unparse(unsigned int v); // NOLINT -std::string Unparse(long v); // NOLINT -std::string Unparse(unsigned long v); // NOLINT -std::string Unparse(long long v); // NOLINT -std::string Unparse(unsigned long long v); // NOLINT -std::string Unparse(float v); -std::string Unparse(double v); - -} // namespace flags_internal - -// ParseFlag() -// -// Parses a string value into a flag value of type `T`. Do not add overloads of -// this function for your type directly; instead, add an `AbslParseFlag()` -// free function as documented above. -// -// Some implementations of `AbslParseFlag()` for types which consist of other, -// constituent types which already have Abseil flag support, may need to call -// `absl::ParseFlag()` on those consituent string values. (See above.) -template <typename T> -inline bool ParseFlag(absl::string_view input, T* dst, std::string* error) { - return flags_internal::InvokeParseFlag(input, dst, error); -} - -// UnparseFlag() -// -// Unparses a flag value of type `T` into a string value. Do not add overloads -// of this function for your type directly; instead, add an `AbslUnparseFlag()` -// free function as documented above. -// -// Some implementations of `AbslUnparseFlag()` for types which consist of other, -// constituent types which already have Abseil flag support, may want to call -// `absl::UnparseFlag()` on those constituent types. (See above.) -template <typename T> -inline std::string UnparseFlag(const T& v) { - return flags_internal::Unparse(v); -} - -// Overloads for `absl::LogSeverity` can't (easily) appear alongside that type's -// definition because it is layered below flags. See proper documentation in -// base/log_severity.h. -enum class LogSeverity : int; -bool AbslParseFlag(absl::string_view, absl::LogSeverity*, std::string*); -std::string AbslUnparseFlag(absl::LogSeverity); - -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_FLAGS_MARSHALLING_H_ |