[no subject]

[Alan Bawden <ALAN at MIT-AI>]

Rubout processing on the LispMachine works at all times, even
in the middle of the wierdest reader macro.  This is because
a read is actually in process as you are typing, when you
type the rubout character a throw is done out of the reader
and it is re-invoked on whatever input is left as soon as you 
stop typing rubouts.  This has the wierd side effect that
syntax errors sometimes cause an error before you are even
finished typing the form.  GSB has a frob that does someting
like this in MacLisp, but for various reasons that he will
be happy to flame about, it cannot actually work in a working
MacLisp environment.