> Weeble  added the comment:
>
> Well, the status quo depends on an unsupported field - "anchor".

Better not repeat the mistake then ?

> As far
> as I can tell, the only other option that allows any customisation of
> cursor behaviour is to re-implement the entire selection system from the
> ground up. Would it be acceptable to detect the Tk version and change
> strategy accordingly?
>

IDLE already reimplements several things, which were useful back then
when it wasn't reimplementing -- just adding functionality. If the
only correct solution is really to reimplement the selection, then it
would be better to do it anyway, but I don't think it is.

I'm interested in knowing how many interactive shells implement this
same behaviour, or if there are that many I would like at least some
examples. I'm unsure about the usefulness of the current functionality
(supposing it was working as intended).

> I don't know how far back this would work: I've tested it with Tk 8.5
> and 8.4.
>

All versions of 8.4 ? I've seen complaints about early releases of tk
8.4 and the use of the unsupported function.