/JavaScript/while.cs

// while.cs

//

// Copyright 2010 Microsoft Corporation

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//     http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.



using System;

using System.Collections.Generic;

using System.Text;



namespace Microsoft.Ajax.Utilities

{

    public sealed class WhileNode : AstNode

    {

        public AstNode Condition { get; private set; }

        public Block Body { get; private set; }



        public WhileNode(Context context, JSParser parser, AstNode condition, AstNode body)

            : base(context, parser)

        {

            Condition = condition;

            Body = ForceToBlock(body);

            if (Condition != null) Condition.Parent = this;

            if (Body != null) Body.Parent = this;

        }



        public override void Accept(IVisitor visitor)

        {

            if (visitor != null)

            {

                visitor.Visit(this);

            }

        }



        public override IEnumerable<AstNode> Children

        {

            get

            {

                return EnumerateNonNullNodes(Condition, Body);

            }

        }



        public override bool ReplaceChild(AstNode oldNode, AstNode newNode)

        {

            if (Condition == oldNode)

            {

                Condition = newNode;

                if (newNode != null) { newNode.Parent = this; }

                return true;

            }

            if (Body == oldNode)

            {

                Body = ForceToBlock(newNode);

                if (Body != null) { Body.Parent = this; }

                return true;

            }

            return false;

        }



        internal override bool RequiresSeparator

        {

            get

            {

                // requires a separator if the body does

                return Body == null || Body.Count == 0 ? false : Body.RequiresSeparator;

            }

        }



        internal override bool EncloseBlock(EncloseBlockType type)

        {

            // pass the query on to the body

            return Body == null ? false : Body.EncloseBlock(type);

        }

    }

}