[Python-Dev] Adding a new class to the library?

[Guido van Rossum]

> I have a candidate for admission to the Python class library.  It's a
> framework class for writing things like menu trees and object
> browsers.  What's the correct approval procedure for such things?
> 
> In more detail, it supports manipulating a stack of sequence objects.
> Each sequence object has an associated selection point (the cirrently
> selected sequence member) and an associated viewport around it (a
> range of indices or sequence members that are considered `visible'.
> 
> There are methods to manipulate the object stack.  More importantly,
> there are functions which move the selection point in the current
> object around, and drag the viewport with it.  (This sort of
> thing sounds simple, but is tricky for the same reason BitBlt is
> tricky -- lots of funky boundary cases.)
> 
> I've used this as the framework for implementing the curses menu
> interface for CML2.  It is well-tested and stable.  It might also
> be useful for implementing other kinds of data browsers in any
> situation where the concept of limited visibility around a selection
> point makes sense.  Symbolic debuggers is an example that leaps to mind.
> 
> I am, of course, willing to fully document it.

Have a look at the tree widget in IDLE.  That's Tk specific, but I
believe there's a lot of GUI independent concepts in there.  IDLE's
path and object browsers are built on it.  How does this compare?

--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)