public static IEdmModel BuildEdmModel(ODataModelBuilder builder)
        {
            if (builder == null)
            {
                throw Error.ArgumentNull("builder");
            }

            EdmModel model = new EdmModel();
            EdmEntityContainer container = new EdmEntityContainer(builder.Namespace, builder.ContainerName);

            // add types and sets, building an index on the way.
            Dictionary<string, IEdmStructuredType> edmTypeMap = model.AddTypes(builder.StructuralTypes);
            Dictionary<string, EdmEntitySet> edmEntitySetMap = model.AddEntitySets(builder.EntitySets, container, edmTypeMap);
            
            // add procedures
            container.AddProcedures(builder.Procedures, edmTypeMap, edmEntitySetMap);

            // finish up
            model.AddElement(container);
            return model;
        }