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POExpression failure
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copied!<p>I've got such expression:</p> <pre><code>Linq2Rest.Reactive.InnerRestObservable`1[A] .Where(item => (Convert(IIF((item != null), item.ID, 0)) == Convert(61))) .Skip(0) .Take(20) </code></pre> <p>When I invoke <a href="http://msdn.microsoft.com/en-us/library/ff402849%28v=vs.103%29.aspx" rel="nofollow">Subscribe method</a> on it I recieve such error:</p> <blockquote> <p>variable 'item' of type 'A' referenced from scope '', but it is not defined</p> </blockquote> <p>Can't figure out what is the problem. Actually can't see any problems with item argument... </p> <p>UPD. Where clause built with this code:</p> <pre><code>public static IQbservable WhereExpression(this IQbservable query, Expression filterExpression, ParameterExpression instance = null) { if (instance == null) instance = Expression.Parameter(query.ElementType, "item"); // NOI18N var filteredQuery = (IQbservable)GenericsHelper.InvokeGenericExtensionMethod( typeof(Qbservable), "Where", // NOI18N new[] { query.ElementType }, query, Expression.Lambda(filterExpression, instance) ); return filteredQuery; } public static object InvokeGenericExtensionMethod( Type extensionClass, string extensionMethodName, Type[] genericTypes, params object[] parameters ) { var method = extensionClass.GetMethods().FirstOrDefault(m => m.Name == extensionMethodName && m.IsGenericMethod && m.GetGenericArguments().Length == genericTypes.Length && m.GetParameters().Length == parameters.Length ); if (method == null) throw new ArgumentException(string.Format("Type {0} doesn't contain method {1}", extensionClass.Name, extensionMethodName)); // NOI18N var genericMethod = method.MakeGenericMethod(genericTypes); return genericMethod.Invoke(null, parameters); } </code></pre> <p>UPD 2. This is how WhereExpression calls:</p> <pre><code>foreach (var filter in filters) { var paramExpression = Expression.Parameter(query.ElementType, "item"); // NOI18N query = query.WhereExpression(filter.CreateFilterExpression(paramExpression), paramExpression); } </code></pre> <p>filters is collection of IFilterDescriptor interface from telerik. </p>

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