> I finally figured out the magic that makes the commands that
> require %-substitutions to work, like so:
>
> my $sub = sub {
> my ($X, $Y) = (Tcl::Ev('X'), Tcl::Ev('Y'));
> print "X: $X Y: $Y\n";
> };
> $mw->bind('<Motion>', \\'XY', $sub);
>
> This double-reference to the scalar seems a little weird to me.
"weirdness" is clearly stated inside Tcl.pm.
This is documented, hence is not a bug :)
But seriously I also dislike \\'XY'
> It would of course be best if we could somehow manage to get the
> substitutions as part of the command.
>
> Now that we properly handle command callbacks with args, I would
> like to recommend this alternative:
>
> $mw->bind('<Motion>', [$sub, Tcl::EV('X', 'Y', ...),
> "foo", ...]);
>
> This would magic convert to the either the same special things
> that requires the Tcl::Ev in the sub, or perhaps (if I can make
> the magic work), have it pass the %-subs to the Tcl side of the
> callback, while maintaining the "foo", ... for the perl side.
>
> Any objections, or better ideas?
I still hope that "correct" method is doable, namely
$mw->bind('<Motion>', \&hadler),
sub handler {
# uses %-subs freely,
print Ev('x');
}
I thought this is quite doable with Ev to do some preparations first (to
manage which results must be stored), and then return an object that, at a
time when its result is needed, retreives it properly.
I remember this could lead to complications, but still I have a feeling that
is is doable.
BTW, probably right now it is the right moment to check how this is
implemented in Ruby or Python.
Vadim.
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