System.Exception: System.InvalidOperationException: Collection was modified; enumeration operation may not execute.

[SlavaRa]

System.Exception: System.InvalidOperationException: Collection was modified; enumeration operation may not execute.
   at System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource)
   at System.Collections.Generic.List`1.Enumerator.MoveNextRare()
   at AS2Context.Context.GetModel(String package, String cname, String inPackage)
   at HaXeContext.Context.ResolveType(String cname, FileModel inFile)
   at ASCompletion.Model.ClassModel.ResolveExtendedType(IList`1 extensionList)
   at ASCompletion.Model.ClassModel.ResolveExtends()
   at HaXeContext.Context.GetCodeModel(FileModel result, String src, Boolean scriptMode)
   at ASCompletion.Context.ASContext.GetFileModel(String fileName)
   at ASCompletion.Model.PathExplorer.ParseFoundFiles()
   at ASCompletion.Model.PathExplorer.BackgroundRun()
   at ASCompletion.Model.PathExplorer.ExploreInBackground()
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()