/Microsoft.Scripting/Interpretation/CommaAddress.cs

/* ****************************************************************************

 *

 * Copyright (c) Microsoft Corporation. 

 *

 * This source code is subject to terms and conditions of the Microsoft Public License. A 

 * copy of the license can be found in the License.html file at the root of this distribution. If 

 * you cannot locate the  Microsoft Public License, please send an email to 

 * dlr@microsoft.com. By using this source code in any fashion, you are agreeing to be bound 

 * by the terms of the Microsoft Public License.

 *

 * You must not remove this notice, or any other, from this software.

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 * ***************************************************************************/

using System; using Microsoft;





using System.Collections.Generic;

#if CODEPLEX_40

using System.Linq.Expressions;

#else

using Microsoft.Linq.Expressions;

#endif



namespace Microsoft.Scripting.Interpretation {

    internal class CommaAddress : EvaluationAddress {

        private List<EvaluationAddress> _addrs;



        internal CommaAddress(BlockExpression address, List<EvaluationAddress> addresses)

            : base(address) {

            _addrs = addresses;

        }



        internal override object GetValue(InterpreterState state, bool outParam) {

            object result = null;

            for (int i = 0; i < _addrs.Count; i++) {

                EvaluationAddress current = _addrs[i];



                if (current != null) {

                    object val = current.GetValue(state, outParam);

                    if (i == Index) {

                        result = val;

                    }

                }

            }

            return result;

        }



        internal override object AssignValue(InterpreterState state, object value) {

            EvaluationAddress addr = _addrs[Index];

            if (addr != null) return addr.AssignValue(state, value);

            return null;

        }



        internal int Index {

            get {

                return ((BlockExpression)Expression).Expressions.Count - 1;

            }

        }

    }

}