8. A system comprising: a processor operable to perform software routines; and a machine-readable medium tangibly embodying shared software routines that include a dialog routine to provide a preview control operable to specify whether effects of interaction with a dialog are to be previewed during the interaction, wherein the dialog routine includes instructions that enable a subset of the interactions to be performed from the dialog independent of a current preview state in the dialog and instructions that cause the subset of the interactions to be undone if the dialog is cancelled.
8. A system comprising: a processor operable to perform software routines; and a machine-readable medium tangibly embodying shared software routines that include a dialog routine to provide a preview control operable to specify whether effects of interaction with a dialog are to be previewed during the interaction, wherein the dialog routine includes instructions that enable a subset of the interactions to be performed from the dialog independent of a current preview state in the dialog and instructions that cause the subset of the interactions to be undone if the dialog is cancelled. 13. The system of claim 8 , wherein the subset of the interactions comprise interactions with a child dialog.