Ouch, my fault. I deleted the wrong bindings.
> On Jul 24, 2017, at 1:58 PM, Philip McGrath <[email protected]> wrote: > > Sorry for the crossed emails. If I understand what's happening correctly, the > code you sent only blames the "deserializing" module because it shaddows > `serialize` and `deserialize` to mean `values`, so the instance is never > actually deserialized or serialized and `deserialize-info:adder-v0` is never > consulted. If I remove the `local` block, the error is displayed in terms of > `+`. > > #lang racket > > (module server racket > (require racket/serialize) > > (provide (contract-out > [adder (-> natural-number/c (-> natural-number/c > natural-number/c))])) > > (struct adder (base) > #:property prop:procedure > (λ (this x) (+ (adder-base this) x)) > #:property prop:serializable > (make-serialize-info (λ (this) (vector (adder-base this))) > #'deserialize-info:adder-v0 > #f > (or (current-load-relative-directory) > (current-directory)))) > > (define deserialize-info:adder-v0 > (make-deserialize-info adder (λ () (error 'adder "can't have cycles")))) > > (module+ deserialize-info > (provide deserialize-info:adder-v0))) > > (require (submod "." server) racket/serialize) > > (define x (serialize (adder 5))) > (displayln x) > (define f (deserialize x)) > (f 'not-a-number) > > -Philip > > On Mon, Jul 24, 2017 at 12:50 PM, Philip McGrath <[email protected]> > wrote: > It occurs to me that one approach is to use the low-level `contract` form > directly. It gives better blame than `define/contract`, at least. The program: > > #lang racket > > (module server racket > (require racket/serialize) > > (provide (contract-out > [adder (-> natural-number/c (-> natural-number/c > natural-number/c))])) > > (struct adder (base) > #:property prop:procedure > (λ (this x) (+ (adder-base this) x)) > #:property prop:serializable > (make-serialize-info (λ (this) (vector (adder-base this))) > #'deserialize-info:adder-v0 > #f > (or (current-load-relative-directory) > (current-directory)))) > > (define deserialize-info:adder-v0 > (make-deserialize-info > (λ (base) > (define inst (adder base)) > (contract (-> natural-number/c natural-number/c) > inst > '(definition adder) > `(deserialization ,inst) > (object-name adder) > #f)) > (λ () (error 'adder "can't have cycles")))) > > (module+ deserialize-info > (provide deserialize-info:adder-v0))) > > (require (submod "." server) racket/serialize) > > ((deserialize (serialize (adder 5))) 'not-a-number) > > reports the error: > > adder: contract violation > expected: natural-number/c > given: 'not-a-number > in: the 1st argument of > (-> natural-number/c natural-number/c) > contract from: (definition adder) > blaming: (deserialization #<procedure:adder>) > (assuming the contract is correct) > > > -Philip > > On Mon, Jul 24, 2017 at 12:35 PM, Philip McGrath <[email protected]> > wrote: > That is precisely the contract violation I'd like to see reported, but, > without the shadowing of serialize and deserialize, the error is reported in > terms of `+`. (And, if it wasn't clear, I do intend to actually read and > write the serialized instance.) > > I (think) I understand why deserialization strips the contract from the > instance: the contract is added at the module boundary using the > chaperone/impersonator infrastructure, and deserialization uses the > unprotected form of `adder` passed to `make-deserialize-info` within the > server module. > > What I don't understand is how to give `make-deserialize-info` a function > that (1) has a contract where (2) fulfilling the range part of the contract > becomes the deserializing module's obligation — if such a thing is possible. > Aside from attempts with `define/contract` (which as I now understand > achieved point 1 but not point 2), I've also tried putting the definition of > `deserialize-info:adder-v0` in a different module, so that its version of > `adder` has a contract, but then the binding isn't seen by > `make-serialize-info`. > > -Philip > > On Mon, Jul 24, 2017 at 7:30 AM, Matthias Felleisen <[email protected]> > wrote: > >> On Jul 23, 2017, at 10:50 PM, Philip McGrath <[email protected]> >> wrote: >> >> If I'm following correctly, I think that's what I was trying to do, but I'm >> unclear how to give `make-deserialize-info` a variant of `make-adder` that >> has a contract. The initial example with `define/contract` was the closest >> I've come: it at least reported violations in terms of `make-adder` rather >> than `+`, but (as I now understand) it blamed the `server` module for all >> violations. >> >> -Philip >> >> On Sun, Jul 23, 2017 at 9:27 PM, Matthew Flatt <[email protected]> wrote: >> The original example had an explicit deserializer: >> >> At Sun, 23 Jul 2017 19:54:43 -0500, Philip McGrath wrote: >> > (define deserialize-info:adder-v0 >> > (make-deserialize-info make-adder >> > (λ () (error 'adder >> > "can't have cycles")))) >> >> You're constructing the deserializer with `make-adder` --- the variant >> from inside the `server` module, so it doesn't have a contract. >> >> I think this is where you want to draw a new boundary by giving >> `make-deserialize-info` a variant of `make-adder` that has a contract. > > > > Don’t you just want this: > > #lang racket > > (module server racket > (require racket/serialize) > > (provide (contract-out > [adder (-> natural-number/c (-> natural-number/c > natural-number/c))])) > > (struct adder (base) > #:property prop:procedure > (λ (this x) (+ (adder-base this) x)) > #:property prop:serializable > (make-serialize-info (λ (this) (vector (adder-base this))) > #'deserialize-info:adder-v0 > #f > (or (current-load-relative-directory) > (current-directory)))) > > (define deserialize-info:adder-v0 > (make-deserialize-info adder (λ () (error 'adder "can't have cycles")))) > > (module+ deserialize-info > (provide deserialize-info:adder-v0))) > > (require (submod "." server) racket/serialize) > > (local ((define serialize values) > (define deserialize values)) > (define x (serialize (adder 5))) > (define f (deserialize x)) > (f 'not-a-number)) > > > > > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. 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