xpcom/string/nsTDependentSubstring.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6 // IWYU pragma: private, include "nsString.h"
   7
   8 #ifndef nsTDependentSubstring_h
   9 #define nsTDependentSubstring_h
  10
  11 #include "nsTSubstring.h"
  12 #include "nsTLiteralString.h"
  13 #include "mozilla/Span.h"
  14
  15 /**
  16  * nsTDependentSubstring_CharT
  17  *
  18  * A string class which wraps an external array of string characters. It
  19  * is the client code's responsibility to ensure that the external buffer
  20  * remains valid for a long as the string is alive.
  21  *
  22  * NAMES:
  23  *   nsDependentSubstring for wide characters
  24  *   nsDependentCSubstring for narrow characters
  25  */
  26 template <typename T>
  27 class nsTDependentSubstring : public nsTSubstring<T> {
  28  public:
  29   typedef nsTDependentSubstring<T> self_type;
  30   typedef nsTSubstring<T> substring_type;
  31   typedef typename substring_type::fallible_t fallible_t;
  32
  33   typedef typename substring_type::char_type char_type;
  34   typedef typename substring_type::char_traits char_traits;
  35   typedef
  36       typename substring_type::incompatible_char_type incompatible_char_type;
  37
  38   typedef typename substring_type::substring_tuple_type substring_tuple_type;
  39
  40   typedef typename substring_type::const_iterator const_iterator;
  41   typedef typename substring_type::iterator iterator;
  42
  43   typedef typename substring_type::comparator_type comparator_type;
  44
  45   typedef typename substring_type::const_char_iterator const_char_iterator;
  46
  47   typedef typename substring_type::string_view string_view;
  48
  49   typedef typename substring_type::index_type index_type;
  50   typedef typename substring_type::size_type size_type;
  51
  52   // These are only for internal use within the string classes:
  53   typedef typename substring_type::DataFlags DataFlags;
  54   typedef typename substring_type::ClassFlags ClassFlags;
  55
  56  public:
  57   void Rebind(const substring_type&, size_type aStartPos,
  58               size_type aLength = size_type(-1));
  59
  60   void Rebind(const char_type* aData, size_type aLength);
  61
  62   void Rebind(const char_type* aStart, const char_type* aEnd);
  63
  64   nsTDependentSubstring(const substring_type& aStr, size_type aStartPos,
  65                         size_type aLength = size_type(-1))
  66       : substring_type() {
  67     Rebind(aStr, aStartPos, aLength);
  68   }
  69
  70   nsTDependentSubstring(const char_type* aData, size_type aLength)
  71       : substring_type(const_cast<char_type*>(aData), aLength, DataFlags(0),
  72                        ClassFlags(0)) {}
  73
  74   explicit nsTDependentSubstring(mozilla::Span<const char_type> aData)
  75       : nsTDependentSubstring(aData.Elements(), aData.Length()) {}
  76
  77   nsTDependentSubstring(const char_type* aStart, const char_type* aEnd);
  78
  79 #if defined(MOZ_USE_CHAR16_WRAPPER)
  80   template <typename Q = T, typename EnableIfChar16 = mozilla::Char16OnlyT<Q>>
  81   nsTDependentSubstring(char16ptr_t aData, size_type aLength)
  82       : nsTDependentSubstring(static_cast<const char16_t*>(aData), aLength) {}
  83
  84   template <typename Q = T, typename EnableIfChar16 = mozilla::Char16OnlyT<Q>>
  85   nsTDependentSubstring(char16ptr_t aStart, char16ptr_t aEnd);
  86 #endif
  87
  88   nsTDependentSubstring(const const_iterator& aStart,
  89                         const const_iterator& aEnd);
  90
  91   // Create a nsTDependentSubstring to be bound later
  92   nsTDependentSubstring() : substring_type() {}
  93
  94   // auto-generated copy-constructor OK (XXX really?? what about base class
  95   // copy-ctor?)
  96   nsTDependentSubstring(const nsTDependentSubstring&) = default;
  97
  98  private:
  99   // NOT USED
 100   void operator=(const self_type&) =
 101       delete;  // we're immutable, you can't assign into a substring
 102 };
 103
 104 extern template class nsTDependentSubstring<char>;
 105 extern template class nsTDependentSubstring<char16_t>;
 106
 107 template <typename T>
 108 inline const nsTDependentSubstring<T> Substring(const nsTSubstring<T>& aStr,
 109                                                 size_t aStartPos,
 110                                                 size_t aLength = size_t(-1)) {
 111   return nsTDependentSubstring<T>(aStr, aStartPos, aLength);
 112 }
 113
 114 template <typename T>
 115 inline const nsTDependentSubstring<T> Substring(const nsTLiteralString<T>& aStr,
 116                                                 size_t aStartPos,
 117                                                 size_t aLength = size_t(-1)) {
 118   return nsTDependentSubstring<T>(aStr, aStartPos, aLength);
 119 }
 120
 121 template <typename T>
 122 inline const nsTDependentSubstring<T> Substring(
 123     const nsReadingIterator<T>& aStart, const nsReadingIterator<T>& aEnd) {
 124   return nsTDependentSubstring<T>(aStart.get(), aEnd.get());
 125 }
 126
 127 template <typename T>
 128 inline const nsTDependentSubstring<T> Substring(const T* aData,
 129                                                 size_t aLength) {
 130   return nsTDependentSubstring<T>(aData, aLength);
 131 }
 132
 133 template <typename T>
 134 const nsTDependentSubstring<T> Substring(const T* aStart, const T* aEnd);
 135
 136 extern template const nsTDependentSubstring<char> Substring(const char* aStart,
 137                                                             const char* aEnd);
 138
 139 extern template const nsTDependentSubstring<char16_t> Substring(
 140     const char16_t* aStart, const char16_t* aEnd);
 141
 142 #if defined(MOZ_USE_CHAR16_WRAPPER)
 143 inline const nsTDependentSubstring<char16_t> Substring(char16ptr_t aData,
 144                                                        size_t aLength);
 145
 146 const nsTDependentSubstring<char16_t> Substring(char16ptr_t aStart,
 147                                                 char16ptr_t aEnd);
 148 #endif
 149
 150 template <typename T>
 151 inline const nsTDependentSubstring<T> StringHead(const nsTSubstring<T>& aStr,
 152                                                  size_t aCount) {
 153   return nsTDependentSubstring<T>(aStr, 0, aCount);
 154 }
 155
 156 template <typename T>
 157 inline const nsTDependentSubstring<T> StringTail(const nsTSubstring<T>& aStr,
 158                                                  size_t aCount) {
 159   return nsTDependentSubstring<T>(aStr, aStr.Length() - aCount, aCount);
 160 }
 161
 162 #endif