Re: [BUG] Eval sets incorrect runtime metainformation

[Philip McGrath]

On 6/28/24 09:20, Andrew Tropin wrote:
> On 2024-06-26 18:06, Philip McGrath wrote:
>
> > On 6/26/24 07:41, Andrew Tropin wrote:>
> > > > > That said, the evaluator does attach so-called "meta-data" information
> > > > > to procedures, such as the procedure name.
> > > > > https://www.gnu.org/software/guile/manual/html_node/Procedure-Properties.html.
> > > > > If you know that you are making a procedure you can insert some
> > > > > meta-data for use by your run-time, in an initial vector alist.  See
> > > > > https://www.gnu.org/software/guile/manual/html_node/Procedure-Properties.html.
> > > > > But that's limited and doesn't take macros, etc into account.
> > >
> > > Yep, that's is why I wrote:
> > >
> > > --8<---------------cut here---------------start------------->8---
> > > The another related problem is that the metainformation is stored in
> > > prodecures properties, but not in variables, which makes it impossible
> > > to implement a proper goto definition in general case.
> > > --8<---------------cut here---------------end--------------->8---
> > >
> > > How hard is to make a generic metainformation, which is attachable to
> > > macros, symbols and other objects of the language, not only to
> > > procedures?
> >
> > Instead of run-time reflection on values, I think an IDE implementing
> > jump to definition should use source location and binding information
> > from syntax objects. That's how DrRacket does it.
>
> If you could share a snippet of code or link to related library or docs,
> it could help to understand better the idea.

I'm not intimately familiar with the implementation, but a key library 
is drracket/check-syntax, documented at [1], which is implemented in the 
[2] Git repository (mostly in the drracket-tool-text-lib directory, but 
with tests etc. elsewhere). The source for the Emacs usage is at [3]. 
You can probably get more useful advice on 
<https://racket.discourse.group>, especially from Robby Findler and Greg 
Hendershot. (Note that, while it requires one-time registration, 
Racket's Discourse instance is configured to be usable as a mailing 
list, including starting new threads by email.)

[1]: 
https://docs.racket-lang.org/drracket-tools/Accessing_Check_Syntax_Programmatically.html
[2]: https://github.com/racket/drracket
[3]: https://github.com/greghendershott/racket-mode/

> I still relatively newbie
> in questions related to snyntax objects and overall scheme's expand.

The Scheme reports leave it to implementations to decide how to 
implement syntax objects and expansion more generally, so you will need 
some Guile-specific code. The procedures documented in [4] seem like a 
good place to start, especially `syntax-source`, `syntax-module`, and 
`syntax-local-binding`. I expect Guile has all of the functionality you 
would need, though some of it might be internal or awkward to use. It is 
possible, though, that you might need or want to enhance the expander: 
Racket's expander is especially feature-rich in this area, in part 
because Racket (MzScheme) was originally created to write DrRacket 
(DrScheme), so this kind of tool support has been a consideration from 
the beginning.

[4]: 
https://www.gnu.org/software/guile/manual/html_node/Syntax-Transformer-Helpers.html

Philip