diff --git a/src/apps/debugger/ids/FunctionID.cpp b/src/apps/debugger/ids/FunctionID.cpp
new file mode 100644
index 0000000000..b1c4ec19b4
--- /dev/null
+++ b/src/apps/debugger/ids/FunctionID.cpp
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "FunctionID.h"
+
+#include "StringUtils.h"
+
+
+FunctionID::FunctionID(const BString& idString)
+	:
+	fIDString(idString)
+{
+}
+
+
+FunctionID::~FunctionID()
+{
+}
+
+
+bool
+FunctionID::operator==(const ObjectID& other) const
+{
+	const FunctionID* functionID = dynamic_cast<const FunctionID*>(&other);
+	return functionID != NULL && fIDString == functionID->fIDString;
+}
+
+
+uint32
+FunctionID::ComputeHashValue() const
+{
+	return StringUtils::HashValue(fIDString);
+}
diff --git a/src/apps/debugger/ids/FunctionID.h b/src/apps/debugger/ids/FunctionID.h
new file mode 100644
index 0000000000..82e469a61e
--- /dev/null
+++ b/src/apps/debugger/ids/FunctionID.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef FUNCTION_ID_H
+#define FUNCTION_ID_H
+
+
+#include <String.h>
+
+#include "ObjectID.h"
+
+
+class FunctionID : public ObjectID {
+public:
+								FunctionID(const BString& idString);
+	virtual						~FunctionID();
+
+	virtual	bool				operator==(const ObjectID& other) const;
+
+protected:
+	virtual	uint32				ComputeHashValue() const;
+
+private:
+			const BString		fIDString;
+};
+
+
+#endif	// FUNCTION_ID_H
diff --git a/src/apps/debugger/ids/FunctionParameterID.cpp b/src/apps/debugger/ids/FunctionParameterID.cpp
new file mode 100644
index 0000000000..48fb6ab76e
--- /dev/null
+++ b/src/apps/debugger/ids/FunctionParameterID.cpp
@@ -0,0 +1,13 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "FunctionParameterID.h"
+
+
+FunctionParameterID::~FunctionParameterID()
+{
+}
+
diff --git a/src/apps/debugger/ids/FunctionParameterID.h b/src/apps/debugger/ids/FunctionParameterID.h
new file mode 100644
index 0000000000..689d5527b5
--- /dev/null
+++ b/src/apps/debugger/ids/FunctionParameterID.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef FUNCTION_PARAMETER_ID_H
+#define FUNCTION_PARAMETER_ID_H
+
+
+#include "ObjectID.h"
+
+
+class FunctionParameterID : public ObjectID {
+public:
+	virtual						~FunctionParameterID();
+};
+
+
+#endif	// FUNCTION_PARAMETER_ID_H
diff --git a/src/apps/debugger/ids/LocalVariableID.cpp b/src/apps/debugger/ids/LocalVariableID.cpp
new file mode 100644
index 0000000000..64d62c1800
--- /dev/null
+++ b/src/apps/debugger/ids/LocalVariableID.cpp
@@ -0,0 +1,13 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "LocalVariableID.h"
+
+
+LocalVariableID::~LocalVariableID()
+{
+}
+
diff --git a/src/apps/debugger/ids/LocalVariableID.h b/src/apps/debugger/ids/LocalVariableID.h
new file mode 100644
index 0000000000..d77d6290d4
--- /dev/null
+++ b/src/apps/debugger/ids/LocalVariableID.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef LOCAL_VARIABLE_ID_H
+#define LOCAL_VARIABLE_ID_H
+
+
+#include "ObjectID.h"
+
+
+class LocalVariableID : public ObjectID {
+public:
+	virtual						~LocalVariableID();
+};
+
+
+#endif	// LOCAL_VARIABLE_ID_H
diff --git a/src/apps/debugger/ids/ObjectID.cpp b/src/apps/debugger/ids/ObjectID.cpp
new file mode 100644
index 0000000000..32b78f3299
--- /dev/null
+++ b/src/apps/debugger/ids/ObjectID.cpp
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include "ObjectID.h"
+
+
+ObjectID::ObjectID()
+	:
+	fHashValue(0)
+{
+}
+
+
+ObjectID::~ObjectID()
+{
+}
diff --git a/src/apps/debugger/ids/ObjectID.h b/src/apps/debugger/ids/ObjectID.h
new file mode 100644
index 0000000000..b1a79bb3cb
--- /dev/null
+++ b/src/apps/debugger/ids/ObjectID.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef OBJECT_ID_H
+#define OBJECT_ID_H
+
+
+#include <Referenceable.h>
+
+
+class ObjectID : public Referenceable {
+public:
+								ObjectID();
+	virtual						~ObjectID();
+
+	inline	uint32				HashValue() const;
+
+	virtual	bool				operator==(const ObjectID& other) const = 0;
+	inline	bool				operator!=(const ObjectID& other) const;
+
+protected:
+	virtual	uint32				ComputeHashValue() const = 0;
+
+protected:
+	mutable	uint32				fHashValue;
+};
+
+
+uint32
+ObjectID::HashValue() const
+{
+	if (fHashValue == 0)
+		fHashValue = ComputeHashValue();
+	return fHashValue;
+}
+
+
+bool
+ObjectID::operator!=(const ObjectID& other) const
+{
+	return !(*this == other);
+}
+
+
+#endif	// OBJECT_ID_H