Putting this program in q.scm (lambda () (let* ((tag (list 'let/ec))) (call-with-prompt tag (lambda () (let lp () (call-with-values h (let () (define (g a b) (let ((kk (nm a u v))) (cond ((equal? kk _filename) (let ((tmp (pylist-ref modules a))) (apply abort tag tmp '()))) ((equal? (end kk) _filename) (let ((tmp (pylist-ref modules a))) (apply abort tag tmp '()))))) (lp)) (define f (case-lambda ((a b) (g a b)) ((a b . y) (g a b)))) f)))) (lambda (xx . results) (apply values results))))) Results in the warning forgot to emit definition instructions? Using the below version of f works without the warning, with slusk = (lambda (g . x) (apply g x)) non inlined in: (define f (case-lambda ((a b) (g a b)) ((a b . y) (slusk g a b)))) Tested in v3.0.8 and main dec 18 2022