> On Sep 8, 2016, at 4:36 PM, Alexis King <lexi.lam...@gmail.com> wrote: > > Alright, I’m finally taking a look at this (and looping the users > list back in). I think, unfortunately, your (Alex’s) change isn’t > quite sufficient: having access to the get-info function isn’t > enough. The read and read-syntax functions need access to the lambda > returned by the base language’s get-info procedure, not the wrapper > function that accepts an input port.
That still shouldn't be a problem with my attempted version. If the `convert-lang` function has access to the old `read-syntax` and the old `get-info` functions (the ones that the base language `provide`s), then it can return a `read-syntax` function that applies the old `get-info` function to the proper arguments to give you what you want. > I just tried my hand at this, and I managed to get a hacky solution > working. I’ve put my version in a gist here: > > https://gist.github.com/lexi-lambda/12b3c23d58937ce66fff03be2adb6e99 > > The above code is almost identical to make-meta-reader from > syntax/module-reader, but the read-fn function is altered to pass > both the underlying read or read-syntax function AND the result of > -get-info to the convert-read function. You can see this on line > 65 of the above gist. > > The interface is still pretty bad, since it requires that users of > the function accept both arguments, so I’d want to clean it up a > lot before putting it in a package somewhere. I don’t have any > immediate plans to do that yet, though, so somebody might find some > use for this code in the meantime. I’ve successfully used this code > to implement a language extension that uses the result of a base > language’s get-info function to direct how reading should work. > > Alexis > >> On Sep 6, 2016, at 9:19 PM, Alex Knauth <alexan...@knauth.org> wrote: >> >> I have no idea whether this works or not; it's completely untested. I took >> the existing implementation of make-meta-reader and tried to manipulate it >> into something that allowed one `convert-lang` function to convert the >> `read`, `read-syntax`, and `get-info` functions together, with each able to >> reference the base-language's versions of the others. I might have made some >> mistakes confusing the get-info function with the function that get-info >> returns, things like that. I have no idea how many of those kinds of errors >> I might have made. > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
