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SketchyLISP
Reference
  Copyright (C) 2006
Nils M Holm

6 Pre-Defined Symbols

6.1 **

** => most recent top-level result

The ** symbol is bound to the normal form of the expression most recently entered at the top level. When attempting to evaluate a term that does not have a normal form -- like

(cdr ())

-- the binding of ** remains unchanged:

(cons 'a 'b)
=> (a . b)
**
=> (a . b)
(car ())
* Top-level[1]: non-pair in 'car': ()
**
=> (a . b)