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(define (make-cached-writer the-db)
(let ((db the-db)
(queue '()))
(lambda (cacheable . qry-params)
(lambda (cacheable . qry-params) ;; fn qry
(if cacheable
(begin
(set! queue (cons qry-params queue))
(set! queue (cons qry-params queue))
(call/cc))
(begin
(print "Starting transaction")
(for-each
(lambda (queue-item)
(let ((fn (car queue-item))
(qry (cdr queue-item)))
(print "WRITE to " db ": " queue-item))
(print "WRITE to " db ": " qry)
)
(reverse queue))
(print "End transaction")
(print "READ from " db ": " qry-params))))))
(define a (make-cached-writer "the db"))
(a #t "insert abc")
(a #t "insert def")
(a #t "insert hij")
(a #f "select foo")
(define *cw* (make-cached-writer "the db"))
(define (dbcall cacheable query)
(*cw* cacheable query))
(dbcall #t "insert abc")
(dbcall #t "insert def")
(dbcall #t "insert hij")
(dbcall #f "select foo")
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