buttonact
BUTTONACT (variable)
if nonempty, should be an instruction list that will be evaluated
whenever a mouse button is pressed. Note that the user may have
released the button before the instructions are evaluated. BUTTON
will still output which button was most recently pressed. CLICKPOS
will output the position of the mouse cursor at the moment the
button was pressed; this may be different from MOUSEPOS if the
user moves the mouse after clicking.
Note that it's possible for the user to press a button during the
evaluation of the instruction list. If this would confuse your
program, prevent it by temporarily setting BUTTONACT to the empty
list. One easy way to do that is the following:
make "buttonact [button.action]
to button.action [:buttonact []]
... ; whatever you want the button to do
end