1. A machine-implemented method comprising: receiving commands resulting from interaction with controls of a software interface dialog; distinguishing between a first command that is held upon receipt, in at least one circumstance, to be performed later, and a second command that is passed through the dialog to be performed upon receipt; and retaining both the first command and the second command in a command sequence managed by a cancel control of the dialog; wherein the dialog includes a preview control operable to specify whether effects of interaction with the controls are to be previewed as interaction with the controls occurs, the first command is subject to the preview control, the second command is not subject to the preview control, the first and second commands being additional to one or more commands affecting the preview control, and the distinguishing comprises performing the second command but not the first command when the preview control specifies the effects of interaction are not to be previewed.
1. A machine-implemented method comprising: receiving commands resulting from interaction with controls of a software interface dialog; distinguishing between a first command that is held upon receipt, in at least one circumstance, to be performed later, and a second command that is passed through the dialog to be performed upon receipt; and retaining both the first command and the second command in a command sequence managed by a cancel control of the dialog; wherein the dialog includes a preview control operable to specify whether effects of interaction with the controls are to be previewed as interaction with the controls occurs, the first command is subject to the preview control, the second command is not subject to the preview control, the first and second commands being additional to one or more commands affecting the preview control, and the distinguishing comprises performing the second command but not the first command when the preview control specifies the effects of interaction are not to be previewed. 2. The method of claim 1 , wherein receiving the commands comprises receiving pass-through and preview commands, including the first and second commands, in any order, and the method further comprises doing and undoing the preview commands in response to changes to the preview control.