10. A computer program product comprising: a non-transitory computer readable storage medium having computer usable program code encoded thereon for diagramming, including instructions which when executed on a computer, cause the computer to: generate a diagram graphically representing a subject model, the subject model having model elements and the diagram being formed of notational elements corresponding to the model elements of the subject model; and in response to a primary edit to the subject model, generate a non-persistent view representative of the primary edit for secondary edits to the diagram, the non-persistent view being contained in a non-persistent container element, that is associated with but detached from a persistent container element of the diagram, said generating including displaying the diagram and the non-persistent view to a user as if the non-persistent view were a persistent part of the diagram by displaying both attributes of the persistent and non-persistent container elements of the diagram; wherein a notation meta-model persists the notational elements with references to the corresponding model elements, the notation meta-model allowing notational elements to be recreated and changed dynamically in a manner free of replacing original notational elements in the diagram by mapping from which persistent and non-persistent container elements to retrieve said attributes, and wherein mapping attributes of the non-persistent container element to the persistent container element transforms the non-persistent view into a persistent view persisting with the diagram.
13. The computer program product as claimed in claim 10 wherein the notation meta-model provides extension of a notational element by aggregation or composition instead of by inheritance.