gecko-dev/xpcom/ds/nsEmptyEnumerator.h

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 * The Original Code is mozilla.org code.
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 * The Initial Developer of the Original Code is
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 * Portions created by the Initial Developer are Copyright (C) 1998
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 * Contributor(s):
 *   L. David Baron <dbaron@dbaron.org>
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/*

  An empty enumerator.

 */

#include "nsISimpleEnumerator.h"
#include "nsIStringEnumerator.h"

////////////////////////////////////////////////////////////////////////

class EmptyEnumeratorImpl : public nsISimpleEnumerator,
                            public nsIUTF8StringEnumerator,
                            public nsIStringEnumerator
{
public:
    EmptyEnumeratorImpl(void);

    // nsISupports interface
    NS_DECL_ISUPPORTS_INHERITED  // not really inherited, but no mRefCnt

    // nsISimpleEnumerator
    NS_DECL_NSISIMPLEENUMERATOR
    NS_DECL_NSIUTF8STRINGENUMERATOR
    // can't use NS_DECL_NSISTRINGENUMERATOR because they share the
    // HasMore() signature
    NS_IMETHOD GetNext(nsAString& aResult);

    static void Shutdown();

private:
    ~EmptyEnumeratorImpl(void);
};