Are the variables *,+, and / bound to recent input in SLIME or Clozure CL?

Question

I was messing around in SLIME (connected a Clozure REPL) when I discovered this:

It looks like the variables +, *, and / are all bound to some variation on recent input, + is the input itself, * is the result of evaluating that input, and / is the result contained in a list.

Is this right? Who is responsible for this, SLIME or Clozure? I couldn't find anything in the SLIME manual.

Thanks!

; SLIME 2010-05-13
CL-USER> +
NIL
CL-USER> *
NIL
CL-USER> /
(NIL)
CL-USER> -
-
CL-USER> +
-
CL-USER> (list 1 2)
(1 2)
CL-USER> +
(LIST 1 2)
CL-USER> /
((LIST 1 2))
CL-USER> (+ 1 2)
3
CL-USER> /
(3)
CL-USER> *
(3)
CL-USER> (* 1 2)
2
CL-USER> *
2
CL-USER> 

Answer 1

Those are all, and more, specified by the Common Lisp standard. Search the environment dictionary for 'Variable'.