#lang scheme (define engine% (class object% (inspect #f) (init-field integer-time) (super-new) (field [oid-size 4]) (define (set-oid-size! size) (set! oid-size size)))) (define engine-interface% (interface ((class->interface engine%)) get-oids set-vector-info! vector-oid-for encode decode set-codec! divine add-diviner!)) (define (engine? v) (is-a? v engine-interface%)) (provide engine? engine% engine-interface%)