Re: keymap inheritance for non-sparse keymaps

[Richard Stallman]

    Couldn't we simply use t for an explicit nil binding ?

Yes, we could.  t is not a legitimate key binding, unless someone
defines it as a command, and it is ok if we tell people not to do
that.

Stefan wrote:

    > Since a keymap entry of t didn't have a defined meaning before (t is not
    > a function) it should be harmless to give it a new meaning.

    I would rather not advertise it, tho.

The data structure is not hidden; users will come across this value.
So we will document what it means.