add support for a nsISimpleEnumerator implementation for nsCOMArray<T> and nsIArray, and update existing interfaces to support that:

- move nsCOMArray_base's ObjectAt/[]/Count() methods into the public so that nsCOMArrayEnumerator can get to it
- tweak NS_NewArray() to match the existing enumerator NS_New* API
- hook up NS_NewArrayEnumerator to nsArray::Enumerate
Not part of the build, for bug 162115

This file was copied in CVS from the following location:
mozilla/xpcom/ds/nsArrayEnumerator.h
Original committer: alecf%netscape.com
Original revision: 1.1
Original date: 2002/10/01 17:34:25

xpcom/glue/nsArrayEnumerator.h

@@ -0,0 +1,84 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* ***** 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 XPCOM Array implementation.
+ *
+ * The Initial Developer of the Original Code
+ * Netscape Communications Corp.
+ * Portions created by the Initial Developer are Copyright (C) 2002
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Alec Flett <alecf@netscape.com>
+ *
+ * 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 ***** */
+
+#ifndef nsArrayEnumerator_h__
+#define nsArrayEnumerator_h__
+
+// enumerator implementation for nsIArray
+
+#include "nsIArray.h"
+#include "nsCOMArray.h"
+#include "nsISimpleEnumerator.h"
+#include "nsCOMPtr.h"
+
+class NS_COM nsSimpleArrayEnumerator : public nsISimpleEnumerator
+{
+public:
+    // nsISupports interface
+    NS_DECL_ISUPPORTS
+
+    // nsISimpleEnumerator interface
+    NS_DECL_NSISIMPLEENUMERATOR
+
+    // nsSimpleArrayEnumerator methods
+    nsSimpleArrayEnumerator(nsIArray* aValueArray) :
+        mValueArray(aValueArray), mIndex(0) {}
+    virtual ~nsSimpleArrayEnumerator(void) {}
+
+protected:
+    nsCOMPtr<nsIArray> mValueArray;
+    PRUint32 mIndex;
+};
+
+
+// Create an enumerator for an existing nsIArray implementation
+// The enumerator holds an owning reference to the array.
+extern NS_COM nsresult
+NS_NewArrayEnumerator(nsISimpleEnumerator* *result,
+                      nsIArray* array);
+
+
+// create an enumerator for an existing nsCOMArray<T> implementation
+// The enumerator will hold an owning reference to each ELEMENT in
+// the array. This means that the nsCOMArray<T> can safely go away
+// without its objects going away.
+extern NS_COM nsresult
+NS_NewArrayEnumerator(nsISimpleEnumerator* *aResult,
+                      const nsCOMArray_base& aArray);
+
+#endif