gecko-dev/intl/locale/MozLocale.h

160 строки
5.1 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode:nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_intl_MozLocale_h__
#define mozilla_intl_MozLocale_h__
#include "nsString.h"
#include "nsTArray.h"
namespace mozilla {
namespace intl {
/**
* Locale class is a core representation of a single locale.
*
* A locale is a data object representing a combination of language, script,
* region, variant and a set of regional extension preferences that may further
* specify particular user choices like calendar, numbering system, etc.
*
* A locale can be expressed as a language tag string, like a simple "fr" for
* French, or a more specific "sr-Cyrl-RS-u-hc-h12" for Serbian in Russia with a
* Cyrylic script, and hour cycle selected to be `h12`.
*
* The format of the language tag follows BCP47 standard and implements a subset
* of it. In the future we expect to extend this class to cover more subtags and
* extensions.
*
* BCP47: https://tools.ietf.org/html/bcp47
*
* The aim of this class it aid in validation, parsing and canonicalization of
* the string.
*
* It allows the user to input any well-formed BCP47 language tag and operate
* on its subtags in a canonicalized form.
*
* It should be used for all operations on language tags, and together with
* LocaleService::NegotiateLanguages for language negotiation.
*
* Example:
*
* Locale loc = Locale("de-at");
*
* ASSERT_TRUE(loc.GetLanguage().Equals("de"));
* ASSERT_TRUE(loc.GetScript().IsEmpty());
* ASSERT_TRUE(loc.GetRegion().Equals("AT")); // canonicalized to upper case
*
*
* Note: The file name is `MozLocale` to avoid compilation problems on
* case-insensitive Windows. The class name is `Locale`.
*/
class Locale {
public:
/**
* The constructor expects the input to be a well-formed BCP47-style locale
* string.
*
* Two operations are performed on the well-formed language tags:
*
* * Case normalization to conform with BCP47 (e.g. "eN-uS" -> "en-US")
* * Underscore delimiters replaced with dashed (e.g. "en_US" -> "en-US")
*
* If the input language tag string is not well-formed, the Locale will be
* created with its flag `mWellFormed` set to false which will make the Locale
* never match.
*/
explicit Locale(const nsACString& aLocale);
explicit Locale(const char* aLocale) : Locale(nsDependentCString(aLocale)){};
const nsCString& GetLanguage() const;
const nsCString& GetScript() const;
const nsCString& GetRegion() const;
const nsTArray<nsCString>& GetVariants() const;
/**
* Returns a `true` if the locale is well-formed, such that the
* Locale object can validly be matched against others.
*/
bool IsWellFormed() const { return mIsWellFormed; }
/**
* Returns a canonicalized language tag string of the locale.
*/
const nsCString AsString() const;
/**
* Compares two locales optionally treating one or both of
* the locales as a range.
*
* In case one of the locales is treated as a range, its
* empty fields are considered to match all possible
* values of the same field on the other locale.
*
* Example:
*
* Locale("en").Matches(Locale("en-US"), false, false) // false
* Locale("en").Matches(Locale("en-US"), true, false) // true
*
* The latter returns true because the region field on the "en"
* locale is being treated as a range and matches any region field
* value including "US" of the other locale.
*/
bool Matches(const Locale& aOther, bool aThisRange, bool aOtherRange) const;
/**
* This operation uses CLDR data to build a more specific version
* of a generic locale.
*
* Example:
*
* Locale("en").AddLikelySubtags().AsString(); // "en-Latn-US"
*/
bool AddLikelySubtags();
/**
* Clears the variants field of the Locale object.
*/
void ClearVariants();
/**
* Clears the region field of the Locale object.
*/
void ClearRegion();
/**
* Marks the locale as invalid which in turns makes
* it to be skipped by most LocaleService operations.
*/
void Invalidate() { mIsWellFormed = false; }
/**
* Compares two locales expecting all fields to match each other.
*/
bool operator==(const Locale& aOther) {
// Note: non-well-formed Locale objects are never
// treated as equal to anything
// (even other non-well-formed ones).
return IsWellFormed() && aOther.IsWellFormed() &&
mLanguage.Equals(aOther.mLanguage) &&
mScript.Equals(aOther.mScript) && mRegion.Equals(aOther.mRegion) &&
mVariants == aOther.mVariants && mPrivateUse == aOther.mPrivateUse;
}
private:
nsAutoCStringN<3> mLanguage;
nsAutoCStringN<4> mScript;
nsAutoCStringN<2> mRegion;
nsTArray<nsCString> mVariants;
nsTArray<nsCString> mPrivateUse;
bool mIsWellFormed = true;
};
} // namespace intl
} // namespace mozilla
DECLARE_USE_COPY_CONSTRUCTORS(mozilla::intl::Locale)
#endif /* mozilla_intl_MozLocale_h__ */