[gambit-list] {Spam?} (Marc + ML:) Extension/patch feedback & inclusion request: Practical custom types in the sexp reader (finally)

Marc Feeley feeley at iro.umontreal.ca
Wed Feb 24 15:37:46 EST 2016


As a solution for the short term, I have moved the macro-read-next-char-or-eof and macro-peek-next-char-or-eof macros to _io#.scm so that they can be used after an (include "~~lib/_gambit#.scm").

So you should be able to easily implement the extension you want locally.

Marc


> On Feb 24, 2016, at 1:04 PM, Adam <adam.mlmb at gmail.com> wrote:
> 
> Guillaume is making an excellent point here. (Reposted below with his permission.)
> 
> (To paraphrase him,) I suggest that https://github.com/feeley/gambit/pull/180 should be included because it's reasonable that users should be able to implement their own hash-sequence extensions.
> 
> We don't need to make a bigger philosophical deal about it than that. This is low-level.
> 
> Also I think all reasonable uses will be about data and not code, and therefore they will not need any line numbering or similar info, so the unwrapping is fine - or easy access to an unwrapping routine (you choose). So finally perhaps the only thing would be to give it a better name, if you want that.
> 
> Please let me know if-when it can be included in Gambit :D
> 
> Thanks!!
> 
> 
> 2016-02-24 21:04 GMT+07:00 Guillaume Cartier <gucartier at gmail.com>:
> Hi Adam,
> 
> I think the main thing I'd say is that from my experience, waiting for Marc to integrate something into Gambit so as "not to use undocumented features", you will wait a long time :) I'd say don't worry too much about using undocumented stuff. I think it is actually a wonderful feature that Gambit exposes its internal stuff, where in many languages you just don't have any access to internals. JazzScheme uses what I'd say is a "healthy" mix of mostly documented features and various undocumented features.
> 
> One reason I say you'll be waiting a long time is that a big design goal in Gambit is to *not* go into unclear how best to implement high-level features. In this Marc is really in-tune with the old R5RS philosophy, which is kinda obvious since he was on the committee :) Regarding that, I think Marc should include the low-level part of your code to implement #\ extensions even if he feels the higher level stuff is unclear.
> 
> Cheers,
> Guillaume
> 
> On Mon, Feb 22, 2016 at 4:29 PM, Adam <adam.mlmb at gmail.com> wrote:
> Dear Guillaume,
> 
> I trust you are well -
> 
> if you have any thoughts about the sexp extension ML topic right now feel free to tell there,
> 
> Thanks :)
> 
> 




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