chickadee » scheme » set-car!

set-car! pair objprocedure

Stores obj in the car field of pair. The value returned by set-car! is unspecified.

(define (f) (list 'not-a-constant-list))
(define (g) '(constant-list))
(set-car! (f) 3)                     ===>  unspecified
(set-car! (g) 3)                     ===>  error