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diff --git a/src/libs/xpcom18a4/xpcom/string/public/nsTPromiseFlatString.h b/src/libs/xpcom18a4/xpcom/string/public/nsTPromiseFlatString.h
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla.
+ *
+ * The Initial Developer of the Original Code is IBM Corporation.
+ * Portions created by IBM Corporation are Copyright (C) 2003
+ * IBM Corporation. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Scott Collins <scc@mozilla.org> (original author)
+ *   Darin Fisher <darin@meer.net>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+
+  /**
+   * NOTE:
+   *
+   * Try to avoid flat strings.  |PromiseFlat[C]String| will help you as a last
+   * resort, and this may be necessary when dealing with legacy or OS calls,
+   * but in general, requiring a null-terminated array of characters kills many
+   * of the performance wins the string classes offer.  Write your own code to
+   * use |nsA[C]String&|s for parameters.  Write your string proccessing
+   * algorithms to exploit iterators.  If you do this, you will benefit from
+   * being able to chain operations without copying or allocating and your code
+   * will be significantly more efficient.  Remember, a function that takes an
+   * |const nsA[C]String&| can always be passed a raw character pointer by
+   * wrapping it (for free) in a |nsDependent[C]String|.  But a function that
+   * takes a character pointer always has the potential to force allocation and
+   * copying.
+   *
+   *
+   * How to use it:
+   *
+   * A |nsPromiseFlat[C]String| doesn't necessarily own the characters it
+   * promises.  You must never use it to promise characters out of a string
+   * with a shorter lifespan.  The typical use will be something like this:
+   *
+   *   SomeOSFunction( PromiseFlatCString(aCString).get() ); // GOOD
+   *
+   * Here's a BAD use:
+   *
+   *  const char* buffer = PromiseFlatCString(aCString).get();
+   *  SomeOSFunction(buffer); // BAD!! |buffer| is a dangling pointer
+   *
+   * The only way to make one is with the function |PromiseFlat[C]String|,
+   * which produce a |const| instance.  ``What if I need to keep a promise
+   * around for a little while?'' you might ask.  In that case, you can keep a
+   * reference, like so
+   *
+   *   const nsPromiseFlatString& flat = PromiseFlatString(aString);
+   *     // this reference holds the anonymous temporary alive, but remember,
+   *     // it must _still_ have a lifetime shorter than that of |aString|
+   *
+   *  SomeOSFunction(flat.get());
+   *  SomeOtherOSFunction(flat.get());
+   *
+   *
+   * How does it work?
+   *
+   * A |nsPromiseFlat[C]String| is just a wrapper for another string.  If you
+   * apply it to a string that happens to be flat, your promise is just a
+   * dependent reference to the string's data.  If you apply it to a non-flat
+   * string, then a temporary flat string is created for you, by allocating and
+   * copying.  In the event that you end up assigning the result into a sharing
+   * string (e.g., |nsTString|), the right thing happens.
+   */
+
+class nsTPromiseFlatString_CharT : public nsTString_CharT
+  {
+    public:
+
+      typedef nsTPromiseFlatString_CharT    self_type;
+
+    private:
+
+      NS_COM void Init( const substring_type& );
+      NS_COM void Init( const abstract_string_type& );
+
+        // NOT TO BE IMPLEMENTED
+      void operator=( const self_type& ) NS_DELETE;
+
+        // NOT TO BE IMPLEMENTED
+      nsTPromiseFlatString_CharT() NS_DELETE;
+
+    public:
+
+      explicit
+      nsTPromiseFlatString_CharT( const substring_type& str )
+        : string_type()
+        {
+          Init(str);
+        }
+
+      explicit
+      nsTPromiseFlatString_CharT( const abstract_string_type& readable )
+        : string_type()
+        {
+          Init(readable);
+        }
+
+      explicit
+      nsTPromiseFlatString_CharT( const substring_tuple_type& tuple )
+        : string_type()
+        {
+          // nothing else to do here except assign the value of the tuple
+          // into ourselves.
+          Assign(tuple);
+        }
+  };
+
+inline
+const nsTPromiseFlatString_CharT
+TPromiseFlatString_CharT( const nsTAString_CharT& str )
+  {
+    return nsTPromiseFlatString_CharT(str);
+  }
+
+  // e.g., PromiseFlatCString(Substring(s))
+inline
+const nsTPromiseFlatString_CharT
+TPromiseFlatString_CharT( const nsTSubstring_CharT& frag )
+  {
+    return nsTPromiseFlatString_CharT(frag);
+  }
+
+  // e.g., PromiseFlatCString(a + b)
+inline
+const nsTPromiseFlatString_CharT
+TPromiseFlatString_CharT( const nsTSubstringTuple_CharT& tuple )
+  {
+    return nsTPromiseFlatString_CharT(tuple);
+  }