Boo.Lang.Compiler.Steps.ProcessMethodBodies.OnExtendedGeneratorExpression C# (CSharp) Метод

        public override void OnExtendedGeneratorExpression(ExtendedGeneratorExpression node)
        {
            BlockExpression block = new BlockExpression(node.LexicalInfo);

            Block body = block.Body;
            Expression e = node.Items[0].Expression;
            foreach (GeneratorExpression ge in node.Items)
            {
                ForStatement fs = new ForStatement(ge.LexicalInfo);
                fs.Iterator = ge.Iterator;
                fs.Declarations = ge.Declarations;

                body.Add(fs);

                if (null == ge.Filter)
                {
                    body = fs.Block;
                }
                else
                {
                    fs.Block.Add(
                        NormalizeStatementModifiers.MapStatementModifier(ge.Filter, out body));
                }

            }
            body.Add(new YieldStatement(e.LexicalInfo, e));

            MethodInvocationExpression mie = new MethodInvocationExpression(node.LexicalInfo);
            mie.Target = block;

            Node parentNode = node.ParentNode;
            bool isGenerator = AstUtil.IsListMultiGenerator(parentNode);
            parentNode.Replace(node, mie);
            mie.Accept(this);

            if (isGenerator)
            {
                parentNode.ParentNode.Replace(
                    parentNode,
                    CodeBuilder.CreateConstructorInvocation(
                        TypeSystemServices.Map(ProcessGenerators.List_IEnumerableConstructor),
                        mie));
            }
        }