As posted on comp.lang.tcl:
panedwindow .p ; pack .p -expand yes -fill both
foreach num {1 2 3} { button .$num -text $num }
.p add .1 .2 .3 -stretch first
.p paneconf .3 -hide 1
The sash between buttons 2 and 3 is still one pixel wide. gettign the mouse
there will show the resize-cursor. The effect of clicking & dragging it seems
to depend on the window-manager and on whether the toplevel was manually
resized by the user. If the latter, then dragging the sash magically dragged
the other sash towards the hidden pane. Otherwise it causes the toplevel to
be resized (but only shrunk, never grown, thus still weird).
