The following program: #; cat foo.scm
(import (scheme base) (scheme write) (scheme case-lambda)) (define foo (case-lambda (() 42) ((test) test))) (write (foo)) (write (foo 1337)) With mit-scheme 12.0.50 does not work on my side. Here is the message I have: ;Unbound variable: make-arity-dispatched-procedure ;To continue, call RESTART with an option number: ; (RESTART 3) => Specify a value to use instead of make-arity-dispatched-procedure. ; (RESTART 2) => Define make-arity-dispatched-procedure to a given value. ; (RESTART 1) => Return to read-eval-print level 1. 2 error> End of input stream reached. ;... aborted Ceterum censeo Carthaginem esse delendam. #;