(begin (define (ZED+ ZEDone ZEDtwo) (cond (#t (+ ZEDone ZEDtwo)) (else err))) (define (ZEDA+B) (cond (#t (ZED+ (ZEDread) (ZEDread))) (else err))) (define (ZEDread) (cond (#t (read)) (else err)))) (display (ZEDA+B))