Re: Problems with syntax-ppss: Was [... Apply `comment-depth' text properties when calling `back_comment'.]

[Stefan Monnier]

>> > Well, given that syntax-ppss is not suitable for fixing back_comment,
>> On the contrary I think it's perfectly suitable.
> You're wrong.

I assume this is an opinion ;-)

> I pointed out several reasons for this in two posts yesterday around
> lunch time (European time).

None of these point to it being unsuitable.  At best they indicate that
it may require some tweaks/bugfixes.

> You've failed to respond in detail to the most serious points, beyond
> saying you haven't encountered them in your testing (so far).

What else do you expect me to say?  In most of those cases, it's
difficult to know what the right/best fix would be before encountering
a concrete problem case.
So I'm not going to "fix" those problems in advance.

> If syntax-ppss were to be amended to be rigorously correct, and hence
> usable from back_comment, I would be delighted.

There's no such thing as rigorously correct.  Your code is not
rigorously correct either, and for the exact same underlying reasons:
the best behavior either depends on the underlying intent or is assumed
to be too costly to be worth the trouble.

Your code faces the exact same problems as syntax-ppss, because they are
fairly fundamental.  You took extra measures to address some of those
problems, and I took extra measures to address some others, that's all,
so the weaknesses of our respective solutions aren't exactly the same.

> But while we have the prospect of infinite recursion,

Trivial to resolve, in my experience.

> and the prospect of the cache being useless (because point-min is
> inside a comment or string),

Trivial to resolve as well.

> the prospects for using syntax-ppss in back_comment don't look bright.

Who's talking about prospects.  I have sent a patch and I'm using it
right now.

> Can you fix these (and other) faults of syntax_ppss?

Go right ahead, if you want to fix them.  Personally I won't bother
until I get a concrete example exposing those problems, so I can decide
what's the best way to fix it.

> Pending such a fix, I take it you wouldn't object to me merging the
> comment-cache branch with master?

I definitely would.


        Stefan