protected override void CloneTo (CloneContext clonectx, Statement t)
		{
			Catch target = (Catch) t;

			if (type_expr != null)
				target.type_expr = (FullNamedExpression) type_expr.Clone (clonectx);

			target.block = clonectx.LookupBlock (block);
		}

 protected override void CloneTo(CloneContext clonectx, Statement target)
 {
     throw new NotSupportedException ();
 }

			public override object Visit (Statement stmt)
			{
				Console.WriteLine ("unknown statement:" + stmt);
				return null;
			}

		public void Add (Statement statement)
		{
			statements.Add (statement);
		}

			public Statement RewriteForDeclarators (BlockContext bc, Statement stmt)
			{
				for (int i = declarators.Count - 1; i >= 0; --i) {
					var d = declarators [i];
					var vd = new VariableDeclaration (d.Variable, type_expr.Location);
					vd.Initializer = d.Initializer;
					vd.IsNested = true;
					vd.dispose_call = CreateDisposeCall (bc, d.Variable);
					vd.dispose_call.Resolve (bc);

					stmt = new Using (vd, stmt, d.Variable.Location);
				}

				declarators = null;
				return stmt;
			}

		public Using (VariableDeclaration decl, Statement stmt, Location loc)
			: base (stmt, loc)
		{
			this.decl = decl;
		}

			protected override Expression ResolveInitializer (BlockContext bc, LocalVariable li, Expression initializer)
			{
				Assign assign;
				if (li.Type == InternalType.Dynamic) {
					initializer = initializer.Resolve (bc);
					if (initializer == null)
						return null;

					initializer = Convert.ImplicitConversionRequired (bc, initializer, TypeManager.idisposable_type, loc);
					if (initializer == null)
						return null;

					var var = LocalVariable.CreateCompilerGenerated (TypeManager.idisposable_type, bc.CurrentBlock, loc);
					assign = new SimpleAssign (var.CreateReferenceExpression (bc, loc), initializer, loc);
					assign.ResolveStatement (bc);

					dispose_call = CreateDisposeCall (bc, var);
					dispose_call.Resolve (bc);

					return assign;
				}

				if (li == Variable) {
					CheckIDiposableConversion (bc, li, initializer);
					dispose_call = CreateDisposeCall (bc, li);
					dispose_call.Resolve (bc);
				}

				return base.ResolveInitializer (bc, li, initializer);
			}

		public TryFinally (Statement stmt, Block fini, Location loc)
			 : base (stmt, loc)
		{
			this.fini = fini;
		}

		public For (Statement init_statement,
			    BooleanExpression test,
			    Statement increment,
			    Statement statement,
			    Location l)
		{
			InitStatement = init_statement;
			Test = test;
			Increment = increment;
			Statement = statement;
			loc = l;
		}

		public StatementList (Statement first, Statement second)
		{
			statements = new List<Statement> () { first, second };
		}

			public ArrayForeach (Foreach @foreach, int rank)
			{
				for_each = @foreach;
				statement = for_each.statement;
				loc = @foreach.loc;
				variable = new LocalVariableReference (for_each.variable, loc);

				counter = new StatementExpression[rank];
				variables = new TemporaryVariableReference[rank];
				length_exprs = new Expression [rank];

				//
				// Only use temporary length variables when dealing with
				// multi-dimensional arrays
				//
				if (rank > 1)
					lengths = new TemporaryVariableReference [rank];
			}

				public Body (TypeSpec type, LocalVariable variable,
								   Expression current, Statement statement,
								   Location loc)
				{
					this.type = type;
					this.variable = new LocalVariableReference (variable, loc);
					this.current = current;
					this.statement = statement;
					this.loc = loc;
				}

		public Foreach (Expression type, LocalVariable var, Expression expr, Statement stmt, Location l)
		{
			this.type = type;
			this.variable = var;
			this.expr = expr;
			statement = stmt;
			loc = l;
		}

        public DynamicEventCompoundAssign(string name, Arguments args, ExpressionStatement assignment, ExpressionStatement invoke, Location loc)
            : base(null, args, loc)
        {
            this.name = name;
            base.binder = this;

            // Used by += or -= only
            type = TypeManager.bool_type;

            condition = new If (
                new Binary (Binary.Operator.Equality, this, new BoolLiteral (true, loc), loc),
                new StatementExpression (invoke), new StatementExpression (assignment),
                loc);
        }

			protected override void CloneTo (CloneContext clonectx, Statement target)
			{
				// Nothing to clone
			}

			public override bool Resolve (BlockContext ec)
			{
				bool is_dynamic = expr.Type == InternalType.Dynamic;

				if (is_dynamic) {
					expr = Convert.ImplicitConversionRequired (ec, expr, TypeManager.ienumerable_type, loc);
				} else if (TypeManager.IsNullableType (expr.Type)) {
					expr = new Nullable.UnwrapCall (expr).Resolve (ec);
				}

				var get_enumerator_mg = ResolveGetEnumerator (ec);
				if (get_enumerator_mg == null) {
					return false;
				}

				var get_enumerator = get_enumerator_mg.BestCandidate;
				enumerator_variable = TemporaryVariableReference.Create (get_enumerator.ReturnType, variable.Block, loc);
				enumerator_variable.Resolve (ec);

				// Prepare bool MoveNext ()
				var move_next_mg = ResolveMoveNext (ec, get_enumerator);
				if (move_next_mg == null) {
					return false;
				}

				move_next_mg.InstanceExpression = enumerator_variable;

				// Prepare ~T~ Current { get; }
				var current_prop = ResolveCurrent (ec, get_enumerator);
				if (current_prop == null) {
					return false;
				}

				var current_pe = new PropertyExpr (current_prop, loc) { InstanceExpression = enumerator_variable }.Resolve (ec);
				if (current_pe == null)
					return false;

				VarExpr ve = var_type as VarExpr;
				if (ve != null) {
					if (is_dynamic) {
						// Source type is dynamic, set element type to dynamic too
						var_type = new TypeExpression (InternalType.Dynamic, var_type.Location);
					} else {
						// Infer implicitly typed local variable from foreach enumerable type
						var_type = new TypeExpression (current_pe.Type, var_type.Location);
					}
				} else if (is_dynamic) {
					// Explicit cast of dynamic collection elements has to be done at runtime
					current_pe = EmptyCast.Create (current_pe, InternalType.Dynamic);
				}

				var_type = var_type.ResolveAsTypeTerminal (ec, false);
				if (var_type == null)
					return false;

				variable.Type = var_type.Type;

				var init = new Invocation (get_enumerator_mg, null);

				statement = new While (new BooleanExpression (new Invocation (move_next_mg, null)),
					new Body (var_type.Type, variable, current_pe, statement, loc), loc);

				var enum_type = enumerator_variable.Type;

				//
				// Add Dispose method call when enumerator can be IDisposable
				//
				if (!enum_type.ImplementsInterface (TypeManager.idisposable_type, false)) {
					if (!enum_type.IsSealed && !TypeManager.IsValueType (enum_type)) {
						//
						// Runtime Dispose check
						//
						var vd = new RuntimeDispose (enumerator_variable.LocalInfo, loc);
						vd.Initializer = init;
						statement = new Using (vd, statement, loc);
					} else {
						//
						// No Dispose call needed
						//
						this.init = new SimpleAssign (enumerator_variable, init);
						this.init.Resolve (ec);
					}
				} else {
					//
					// Static Dispose check
					//
					var vd = new Using.VariableDeclaration (enumerator_variable.LocalInfo, loc);
					vd.Initializer = init;
					statement = new Using (vd, statement, loc);
				}

				return statement.Resolve (ec);
			}