Sorry I missed this:
On Dec 8, 2014, at 6:45 PM, George Neuner <[email protected]> wrote:
> and code in the <body> needs to reference “db"
(define (boiler-plate/f f)
(define err-msg #f)
(let/ec fail-network
(with-handlers ([exn:fail:network?
(lambda (e)
(set! err-msg "database connection error")
(fail-network err-msg))])
(let ([db (connect-database)])
(define (thunk)
(f db))
(let/ec fail-sql
(with-handlers ([exn:fail:sql?
(lambda (e)
(let ([info (exn:fail:sql-info e)])
(set! err-msg (cdr (assoc 'message info)))
(fail-sql err-msg)))])
(call-with-transaction db thunk #:isolation 'repeatable-read))
(disconnect db)
err-msg)))))
(define-syntax-rule (boiler-plate db body ...)
(boiler-plate/f (λ (db) body ...)))
(let ()
(define err-msg
(boiler-plate
db
< body ... >
))
; err-msg needed here
err-msg
)
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