wtf/text/StringOperators.h

   1 /*
   2  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
   3  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Library General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Library General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Library General Public License
  16  * along with this library; see the file COPYING.LIB.  If not, write to
  17  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  18  * Boston, MA 02110-1301, USA.
  19  *
  20  */
  21
  22 #ifndef StringOperators_h
  23 #define StringOperators_h
  24
  25 namespace WTF {
  26
  27 template<typename StringType1, typename StringType2>
  28 class StringAppend {
  29 public:
  30     StringAppend(StringType1 string1, StringType2 string2)
  31         : m_string1(string1)
  32         , m_string2(string2)
  33     {
  34     }
  35
  36     operator String() const
  37     {
  38         RefPtr<StringImpl> resultImpl = tryMakeString(m_string1, m_string2);
  39         if (!resultImpl)
  40             CRASH();
  41         return resultImpl.release();
  42     }
  43
  44     operator AtomicString() const
  45     {
  46         return operator String();
  47     }
  48
  49     void writeTo(UChar* destination)
  50     {
  51         StringTypeAdapter<StringType1> adapter1(m_string1);
  52         StringTypeAdapter<StringType2> adapter2(m_string2);
  53         adapter1.writeTo(destination);
  54         adapter2.writeTo(destination + adapter1.length());
  55     }
  56
  57     unsigned length()
  58     {
  59         StringTypeAdapter<StringType1> adapter1(m_string1);
  60         StringTypeAdapter<StringType2> adapter2(m_string2);
  61         return adapter1.length() + adapter2.length();
  62     }
  63
  64 private:
  65     StringType1 m_string1;
  66     StringType2 m_string2;
  67 };
  68
  69 template<typename StringType1, typename StringType2>
  70 class StringTypeAdapter<StringAppend<StringType1, StringType2> > {
  71 public:
  72     StringTypeAdapter<StringAppend<StringType1, StringType2> >(StringAppend<StringType1, StringType2>& buffer)
  73         : m_buffer(buffer)
  74     {
  75     }
  76
  77     unsigned length() { return m_buffer.length(); }
  78     void writeTo(UChar* destination) { m_buffer.writeTo(destination); }
  79
  80 private:
  81     StringAppend<StringType1, StringType2>& m_buffer;
  82 };
  83
  84 inline StringAppend<const char*, String> operator+(const char* string1, const String& string2)
  85 {
  86     return StringAppend<const char*, String>(string1, string2);
  87 }
  88
  89 inline StringAppend<const char*, AtomicString> operator+(const char* string1, const AtomicString& string2)
  90 {
  91     return StringAppend<const char*, AtomicString>(string1, string2);
  92 }
  93
  94 template<typename T>
  95 StringAppend<String, T> operator+(const String& string1, T string2)
  96 {
  97     return StringAppend<String, T>(string1, string2);
  98 }
  99
 100 template<typename U, typename V, typename W>
 101 StringAppend<U, StringAppend<V, W> > operator+(U string1, const StringAppend<V, W>& string2)
 102 {
 103     return StringAppend<U, StringAppend<V, W> >(string1, string2);
 104 }
 105
 106 } // namespace WTF
 107
 108 #endif // StringOperators_h