Tier 3 implements Poetics, the Poet Integrated Construction Set.
The tools in Poetics are meant to be used to examine, debug, and
perhaps even modify a running Poet program. This code is
experimental and not ready for use by the end-user, but it can be very
handy for the Poet developer.
When Poetics is enabled (by setting ::env(POET_TIER)
to 3 prior to loading the Poet package), each widget will have a
right-click popup menu that can be used to select it or any of the
shell widgets that contain it, all the way up to the toplevel. Also,
each widget will respond to the F7 key and
open the Poetics toolbox, which currently has buttons to open the
primary Poetics tools, the object editor and the code browser (these
can also be opened from the popup menu). You can also open a
command console, tkcon is used if it is available (the debugging support within Poetics assumes tkcon is present).
Poetics uses drag-and-drop extensively. If you want to view the
source code to a method, find it in the object editor and drag its icon
onto the text entry in the upper right corner of an open code editor.
The Poetics toolbox has places where you can drop an icon called pockets, you can drop something here and then drag it to another window later.
Not much documentation has been written on the Poetics tools yet, so play around with them to see what they can do.