Nagram/TMessagesProj/jni/voip/webrtc/base/i18n/message_formatter.h
2020-09-30 16:48:47 +03:00

129 lines
4.3 KiB
C++

// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef BASE_I18N_MESSAGE_FORMATTER_H_
#define BASE_I18N_MESSAGE_FORMATTER_H_
#include <stdint.h>
#include <memory>
#include <string>
#include "base/i18n/base_i18n_export.h"
#include "base/macros.h"
#include "base/strings/string16.h"
#include "base/strings/string_piece.h"
#include "third_party/icu/source/common/unicode/uversion.h"
U_NAMESPACE_BEGIN
class Formattable;
U_NAMESPACE_END
namespace base {
class Time;
namespace i18n {
class MessageFormatter;
namespace internal {
class BASE_I18N_EXPORT MessageArg {
public:
MessageArg(const char* s);
MessageArg(StringPiece s);
MessageArg(const std::string& s);
MessageArg(const string16& s);
MessageArg(int i);
MessageArg(int64_t i);
MessageArg(double d);
MessageArg(const Time& t);
~MessageArg();
private:
friend class base::i18n::MessageFormatter;
MessageArg();
// Tests if this argument has a value, and if so increments *count.
bool has_value(int* count) const;
std::unique_ptr<icu::Formattable> formattable;
DISALLOW_COPY_AND_ASSIGN(MessageArg);
};
} // namespace internal
// Message Formatter with the ICU message format syntax support.
// It can format strings (UTF-8 and UTF-16), numbers and base::Time with
// plural, gender and other 'selectors' support. This is handy if you
// have multiple parameters of differnt types and some of them require
// plural or gender/selector support.
//
// To use this API for locale-sensitive formatting, retrieve a 'message
// template' in the ICU message format from a message bundle (e.g. with
// l10n_util::GetStringUTF16()) and pass it to FormatWith{Named,Numbered}Args.
//
// MessageFormat specs:
// http://icu-project.org/apiref/icu4j/com/ibm/icu/text/MessageFormat.html
// http://icu-project.org/apiref/icu4c/classicu_1_1DecimalFormat.html#details
// Examples:
// http://userguide.icu-project.org/formatparse/messages
// message_formatter_unittest.cc
// go/plurals inside Google.
// TODO(jshin): Document this API in md format docs.
// Caveat:
// When plural/select/gender is used along with other format specifiers such
// as date or number, plural/select/gender should be at the top level. It's
// not an ICU restriction but a constraint imposed by Google's translation
// infrastructure. Message A does not work. It must be revised to Message B.
//
// A.
// Rated <ph name="RATING">{0, number,0.0}<ex>3.2</ex></ph>
// by {1, plural, =1{a user} other{# users}}
//
// B.
// {1, plural,
// =1{Rated <ph name="RATING">{0, number,0.0}<ex>3.2</ex></ph>
// by a user.}
// other{Rated <ph name="RATING">{0, number,0.0}<ex>3.2</ex></ph>
// by # users.}}
class BASE_I18N_EXPORT MessageFormatter {
public:
static string16 FormatWithNamedArgs(
StringPiece16 msg,
StringPiece name0 = StringPiece(),
const internal::MessageArg& arg0 = internal::MessageArg(),
StringPiece name1 = StringPiece(),
const internal::MessageArg& arg1 = internal::MessageArg(),
StringPiece name2 = StringPiece(),
const internal::MessageArg& arg2 = internal::MessageArg(),
StringPiece name3 = StringPiece(),
const internal::MessageArg& arg3 = internal::MessageArg(),
StringPiece name4 = StringPiece(),
const internal::MessageArg& arg4 = internal::MessageArg(),
StringPiece name5 = StringPiece(),
const internal::MessageArg& arg5 = internal::MessageArg(),
StringPiece name6 = StringPiece(),
const internal::MessageArg& arg6 = internal::MessageArg());
static string16 FormatWithNumberedArgs(
StringPiece16 msg,
const internal::MessageArg& arg0 = internal::MessageArg(),
const internal::MessageArg& arg1 = internal::MessageArg(),
const internal::MessageArg& arg2 = internal::MessageArg(),
const internal::MessageArg& arg3 = internal::MessageArg(),
const internal::MessageArg& arg4 = internal::MessageArg(),
const internal::MessageArg& arg5 = internal::MessageArg(),
const internal::MessageArg& arg6 = internal::MessageArg());
private:
MessageFormatter() = delete;
DISALLOW_COPY_AND_ASSIGN(MessageFormatter);
};
} // namespace i18n
} // namespace base
#endif // BASE_I18N_MESSAGE_FORMATTER_H_