Re: Bug #22983 (syntax-ppss returns wrong result) is still open. Could we fix it before the release, please.

[Alan Mackenzie]

Hello, Stefan.

On Sat, Jun 11, 2016 at 05:49:59PM -0400, Stefan Monnier wrote:
> > That one thing is to determine, possibly from a cache, the equivalent to

> >     (parse-partial-sexp "1" pos)

> > , where "1" may take non-canonical values.

> > Use cases for font-lock-dont-widen, existing or not, HAVE NO BEARING on
> > that determination of the parse-partial-sexp equivalent.  So why are we
> > talking about them here?

> We're talking about them because the cases where font-lock-dont-widen is
> needed are conceptually the same as those where syntax-ppss would need
> something else than 1, .....

_Some_ of the use cases might exhibit this conceptual similarity.  Some
won't.

Can we please not mix up the use cases with the specification?

> .... so we'd like to come up with something that can cover both uses
> at the same time, so as to have a single setting rather than code that
> sets font-lock-dont-widen, jit-lock-dont-widen, syntax-ppss-base,
> widen-user-limit, and whatnot.

That's entirely the Wrong Thing to do.  We want syntax-ppss not to have
ugly couplings with other functions.  If, as a programmer, I want, say,
to set "1" to 1, I want to be able to do this without fouling up the
functionality of all these other things.  Otherwise the function is less
useful than it should be.

If it turns out in some circumstances that several variables have the
same value, we can set each of them.  It's no big deal.  We could even
use a macro to do it.

Yet again, can we please agree on a strong coherent specification for
syntax-ppss, independent of its use cases, and get that coded up?

Thanks!

>         Stefan

-- 
Alan Mackenzie (Nuremberg, Germany).