intl/lwbrk/WordBreaker.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5 #ifndef mozilla_intl_WordBreaker_h__
   6 #define mozilla_intl_WordBreaker_h__
   7
   8 #include <cstdint>
   9
  10 #define NS_WORDBREAKER_NEED_MORE_TEXT -1
  11
  12 namespace mozilla {
  13 namespace intl {
  14
  15 struct WordRange {
  16   uint32_t mBegin;
  17   uint32_t mEnd;
  18 };
  19
  20 class WordBreaker final {
  21  public:
  22   // WordBreaker is a utility class with only static methods. No need to
  23   // instantiate it.
  24   WordBreaker() = delete;
  25   ~WordBreaker() = delete;
  26
  27   // Find the word boundary by scanning forward and backward from aPos.
  28   //
  29   // @return WordRange where mBegin equals to the offset to first character in
  30   // the word and mEnd equals to the offset to the last character plus 1. mEnd
  31   // can be aLen if the desired word is at the end of aText.
  32   //
  33   // If aPos is already at the end of aText or beyond, both mBegin and mEnd
  34   // equals to aLen.
  35   static WordRange FindWord(const char16_t* aText, uint32_t aLen,
  36                             uint32_t aPos);
  37
  38   // Find the next word break opportunity starting from aPos + 1. It can return
  39   // aLen if there's no break opportunity between [aPos + 1, aLen - 1].
  40   //
  41   // If aPos is already at the end of aText or beyond, i.e. aPos >= aLen, return
  42   // NS_WORDBREAKER_NEED_MORE_TEXT.
  43   //
  44   // DEPRECATED: Use WordBreakIteratorUtf16 instead.
  45   static int32_t Next(const char16_t* aText, uint32_t aLen, uint32_t aPos);
  46
  47  private:
  48   enum WordBreakClass : uint8_t {
  49     kWbClassSpace = 0,
  50     kWbClassAlphaLetter,
  51     kWbClassPunct,
  52     kWbClassHanLetter,
  53     kWbClassKatakanaLetter,
  54     kWbClassHiraganaLetter,
  55     kWbClassHWKatakanaLetter,
  56     kWbClassScriptioContinua
  57   };
  58
  59   static WordBreakClass GetClass(char16_t aChar);
  60 };
  61
  62 }  // namespace intl
  63 }  // namespace mozilla
  64
  65 #endif /* mozilla_intl_WordBreaker_h__ */