Re: frame-local variables weirdness

[Miles Bader <miles.bader@necel.com>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:
> Agreed.  In this sense, specifiers are halfway between frame-local variables
> and using frame-parameter: like using frame-parameter they do require the
> programmer to expect that the variable is going to be made local to
> something, but like frame-local variables they do not require the programmer
> to know to what kind of thing it's going to be made local (it can be made
> buffer-local, frame-local, window-local, buffer-position-local, ... without
> changes to the code).

That's not "halfway" though.

There's a huge leap from "bog standard global variable" to "special
variable-like-form intended to accessed in a context-dependent way".

I think most programmers will either not be aware of the issue, or will
be reluctant to use such a special form in most cases (with good reason,
if the result is less readable).  In any case, the effect is the same,
that the "availability" of variables for context-specific user
customization of such a system will be much poorer than the current
system.

> Basically, this new proposal is trying to focus on the one issue which
> I believe is key: mixing object-local bindings with let-bindings is a source
> of pain and bugs.

I don't really know the implementation details, so I can't really say.

[Despite the fact that that elisp uses shallow binding, I still seem to
assume deep binding in my mental model of how lisp variables work, and
such mixed usage doesn't seem to be a problem for deep binding... :-]

-Miles

-- 
o The existentialist, not having a pillow, goes everywhere with the book by
  Sullivan, _I am going to spit on your graves_.