gistfile1.txt

-> (set-first (set-add s (lambda (x) 3)))
; s: broke its contract
;   promised a procedure that accepts 1 mandatory argument without any keywords
;   produced: 2
;   in: the range of
;       a disjunct of
;       the set-first method of
;       the range of
;       a disjunct of
;       the set-add method of
;       the 2nd conjunct of
;       a disjunct of
;       the 1st conjunct of
;       (set/c (-> number? number?))
;   contract from: (definition s)
;   blaming: (definition s)
;   at: readline-input:54.17
; [,bt for context]