Re: Default for lexical-binding

[Björn Bidar]

Richard Stallman <rms@gnu.org> writes:

> Eventually the default for lexical-binding should become t.  But we
> should not rush this.  We should be kind to people who have used Emacs
> Lisp for decades.

How many are there these days?


> The transient effect of an incompatible change is frustration and
> sometimes trouble, so when the change is worth making, we should plan
> to do it in a way that minimizes the frustration and trouble.  Usually
> that means doing things step by step.

Lexical scoping was introduced in Emacs 24, the change has been quite
gradual I think.

>
> That is where we should leave matters.  We should never desupport
> -*-lexical-binding: nil-*-.  Doing so would require users to make
> substantial changes in old programs to get them to run again.  The
> minuscule saving of space in files would not be worth resulting
> hassles.  The code and documentation of Emacs would hardly get any
> simpler, since dynamic variables would still exist and still have to
> be documented.

I don't maintain the lisp engine of Emacs but if supporting non lexical
binding would hold back modernizing Emacs's Lips would that be a reason
to remove it?