+(define-custom-set-types peers
+ #:elem? Peer?
+ (λ (p1 p2)
+ (equal? (Peer-uri-str p1)
+ (Peer-uri-str p2)))
+ (λ (p)
+ (equal-hash-code (Peer-uri-str p))))
+; XXX Without supplying above explicit hash procedure, we INTERMITTENTLY get
+; the following contract violations:
+;
+; custom-elem-contents: contract violation
+; expected: custom-elem?
+; given: #f
+; context...:
+; /usr/share/racket/collects/racket/private/set-types.rkt:104:0: custom-set->list
+; /home/siraaj/proj/pub/tt/tt.rkt:716:0: crawl
+; /usr/share/racket/collects/racket/cmdline.rkt:191:51
+; body of (submod "/home/siraaj/proj/pub/tt/tt.rkt" main)
+;
+; TODO Investigate why and make a minimal reproducible test case.
+