bug#6203: Frame-local variables break let-binding

[Stefan Monnier]

> This all raises the issue, though: what's the accepted replacement for
> frame-local variables,

frame-parameters

> and why are they deprecated in the first place?

Because OT1H they're very little used, and OTOH they're a pain in the
rear to support and maintain because of all kinds of corner cases, and
it'll only get better with the addition of concurrency and/or
lexical scoping.

> My package has rather a few of them, and it's very useful to be able
> to use them like variables.  I want to make them available for user
> customization, let-bind them, and use them without having to go
> through lots of manual frame-parameter rigamarole each time.  I would
> rather not break any user customizations using these variables.
> So what should I do?

Use frame-parameters.  Note that until Emacs-24 is released, that gives
you a fair bit of time to deal with it.


        Stefan