Nesting behvior of tkwait

Hi all,
I'm concerned about some potential pitfalls I might run into using the
tkwait command. It seems like a very useful command, especially the "tkwait
variable" option. However, I'm wondering if it's dangerous to use "tkwait
variable" inside a procedure called by a binding. I tried this little
experiment:

button .button1 -text "1" -command "waitVar 1"
button .button2 -text "2" -command "waitVar 2"
button .continue -text "CONTINUE" -command "incr cont"
text .text -height 1m
pack .text -side bottom
pack .continue .button2 .button1 -side bottom -fill x
set var1 0; set var2 0; set cont 0
proc waitVar {num} {
tkwait variable cont
.text insert end $num
}

When run, this seems to allow a queue of commands to be built up. If press
"1" three times, I get three 1's when I press continue. If I press "1212"
then continue, I get "2121" in the text box. This is the behavior I'd
expect (I think).

Now, If I change the proc to the following:
proc waitVar {num} {
set cont $num
tkwait variable cont
.text insert end $num
}

If I press "111", I'd expect to get this displayed in the text box when I
press "2". It seems that pressing "2" would cause "cont" to change, which
should trigger the "tkwait variable" statements, and allow the "111" to be
displayed. Why does this not seem to be the case? My only hunch is that,
even though "cont" has been updated, the whole thing won't trigger until the
process that updates "cont" exits. If that's the case, is there any way to
force the triggering?

Thanks,
Dave




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