[racket-dev] backwards incompatibility (was Re: `define-serializable-struct` and the `deserialize-info...` export)

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Fri Nov 8 20:13:59 EST 2013

Yes. Even if (as in the future) the current ring-0 packages weren't all
the same git repository, I'd certainly at least try building them with
this change.

I think that running all the tests in the same way that DrDr does is
not yet easy, but I hope we're moving in the direction of making that
easier, and then my process can improve.

For now: I build, run some tests, and then push --- hoping that I can
fix or revert quickly when DrDr uncovers problems.

At Fri, 8 Nov 2013 13:39:25 -0600, Robby Findler wrote:
> (I think it is okay.)
> But here's a chance for me to point out something I heard about in a
> conversation with Satnam Singh at OOPSLA about how Google works that it
> seems like would be a nice fit for us. Here's my adaptation to our world:
> when you push out what some might consider a change that breaks clients
> (like this one where you also hope to avoid a new package) you are obliged
> to submit pull requests on all ring-0 packages to (at a min) get all test
> cases to pass.
> I guess you did that here, at least for the ring-0 packages in the racket
> git repo, which is where the "I found ..." comment comes from?
> Robby
> On Fri, Nov 8, 2013 at 12:35 PM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
> > Currently, `(define-serializable-struct id ....)` expands to `(provide
> > deserialize-info:id-v0)`. The `deserialize-info...` identifier needs to
> > be exported to make things work, but the export is a hassle: the
> > programmer doesn't care about it, it's not usually documented,
> > re-exporting modules don't want to re-export it, and so on.
> >
> > I'm planning to change `define-serializable-struct` so that the export
> > is put in a `deserialize-info` submodule, where it should cause less
> > trouble. This is a slightly backward-incompatible change; I found a
> > couple of modules that explicitly excluded `deserialize-info...` on
> > import, and so those exclusions would have to be dropped.
> >
> > The change could also be backward-incompatible by changing the protocol
> > for providers of deserialization other than `define-serializeable-struct`.
> > That problem is easier to address: `deserialize` can try a
> > `deserialze-info` submodule first, and if the export isn't found, then
> > it can try the original module.
> >
> > Ok?
> >
> > _________________________
> >   Racket Developers list:
> >   http://lists.racket-lang.org/dev
> >

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