1 files changed, 79 insertions, 0 deletions
diff --git a/kjs/scope_chain.h b/kjs/scope_chain.h
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+++ b/kjs/scope_chain.h
@@ -0,0 +1,79 @@
+/*
+ *  This file is part of the KDE libraries
+ *  Copyright (C) 2003 Apple Computer, Inc.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public License
+ *  along with this library; see the file COPYING.LIB.  If not, write to
+ *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ *  Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef KJS_SCOPE_CHAIN_H
+#define KJS_SCOPE_CHAIN_H
+
+#include "global.h"
+
+namespace KJS {
+
+    class ObjectImp;
+
+/**
+* A scope chain node.
+*/
+    class KJS_EXPORT ScopeChainNode {
+    public:
+        ScopeChainNode(ScopeChainNode *n, ObjectImp *o)
+            : next(n), object(o), refCount(1) { }
+
+        ScopeChainNode *next;
+        ObjectImp *object;
+        int refCount;
+    };
+
+/**
+* A scope chain object.
+*/
+    class KJS_EXPORT ScopeChain {
+    public:
+        ScopeChain() : _node(0) { }
+        ~ScopeChain() { deref(); }
+
+        ScopeChain(const ScopeChain &c) : _node(c._node)
+            { if (_node) ++_node->refCount; }
+        ScopeChain &operator=(const ScopeChain &);
+
+        bool isEmpty() const { return !_node; }
+        ObjectImp *top() const { return _node->object; }
+        ObjectImp *bottom() const { const ScopeChainNode *n = _node;
+				    while (n->next) n = n->next;
+				    return n->object; }
+
+        void clear() { deref(); _node = 0; }
+        void push(ObjectImp *);
+        void pop();
+
+        void mark();
+
+    private:
+        ScopeChainNode *_node;
+
+        void deref() { if (_node && --_node->refCount == 0) release(); }
+        void ref() const;
+
+        void release();
+    };
+
+} // namespace KJS
+
+#endif // KJS_SCOPE_CHAIN_H