TODO list for tcltk package
This site is intended as an intermediate repository for more or
less finalized ideas and plans for the R statistical system. Most
parts of the site are open to the public, and we welcome discussions
on the ideas, but please do not take them for more than that, in
particular there is no commitment to actually carry out the plans in
finite time unless expressedly stated.
Language
- Some types of variables are not easily handled, notably list
variables used by listboxes.
Event handling
The event loop issues needs to be looked at carefully. I suspect
we haven't quite understood the notifier structure, and the
consequences for the main loop on each platform. Some specific issues
are listed below:
- The event loop is polling where it could have been event driven.
- Creating a standalone application (no command line) is tricky.
You can do it with
tkwait.variable() but that seems wrong. There ought to be a way to
run the Tcl event loop without the ordinary input handler. In fact, it
is suspicious that tkwait.variable() works, because it indicates that
*something* is running an event loop of its own...
- We need a clean way to take over the standard i/o channels,
preferably including the readline stuff, so as to Tk-ify the console.
- Some strange slowness occasionally, on Unix this hits when using
menu separators. (The tkcanvas demo was terribly slow on Windows ---
still so?)
- We may need to be more careful with asynchronous event handling.
The separate thread on Windows seems to be interfering with some
programming techniques. E.g. in Tcl you can generally set up the
text/scrollbar protocol with two widget commands even though they need
to refer to eachother, but in R/tcltk you need a configure step after
the widget creation. It might be useful to have a mechanism to disable
event handling while setup is in progress.