Excerpts from Sergey Manucharian's message of Fri Jul 01 13:58:28 -0600 2011:
I do understand what the OP wants. You press Alt-Tab (but don't release) - xmonad switches to another workspace you want just to take look, e.g. if gcc has finished compiling, then you release Alt-Tab and return to the original workspace.
That would save extra Alt-Tab press. Could be useful, I agree, but not sure how to implement it.
Correction: he was talking about the windows, not workspaces, but the idea is the same.
Yes the workspace one is Actions.CycleRecentWS and AFAIK the closest to what was requested for windows is the previously mentioned cycleRecentWindows from Actions.CycleWindows. The windows one isn't very comfortable for many layouts however, since it uses stack order, grabbing "previous" and "next" windows from elsewhere and putting the old focused window below or above the grabbed window. So in Full it makes sense, and for some workflows in other layouts it's helpful. It also allows "previewing without altering stack order" like cycleRecentWS, and enables picking the nth window up or down with a number key. There are several interpretations of what should be done with the window that was where the alt-tabbed new window goes. Should they swap? Should they act like they're stacked in the frame and one hides the other? In some layouts there are tools in CycleWindows to make these latter two happen too. regards, wmw