Re: Default lexical-binding to t

[Richard Stallman <rms@gnu.org>]

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  > > I believe by the time Emacs-31 will be released, such files will be
  > > uncommon, and it is easy to fix them (either by adjusting he code, or
  > > by slapping a `lexical-binding` cookie).

  > I support this, together with the idea of having a warning when loading
  > file without the cookie.  We can always remove the warning (and the
  > cookies) in the future when/if we feel it's time.

If the goal is to lead ysers to indicate this explicitly in each file,
it is enough to complain about files that lack a file local variable
specification for this variable.  It could do this whenever it visits
a file in Emacs Lisp mode.

If we want to increase the pressure to label old files explicitly,
we could go beyond a warning.  For instance, we could ask the user
whether. "Is this an old file thjt is supposed to use dynamic binding?"

If the user answers yes to that, Emacs could offer to modify the file,
adding a tag.

By contrast, to change the interpretation of files that don't specify
the variable is ineffective for the purpuse.  But it will waste a lot
of long-time users' time in figuring out what went wrong.

Eli wrote:

  > If we urge people to specify lexical-binding in their files, then what
  > is the point of making lexical-binding the default?

Perhaps there is no reason to change the default itself ;-).  Perhaps
what we _should_ want is to put an end, among somewhat-maintained
programs, to dependence on the old defaull.

The methods described above will do the job better and faster than
changing the default, and much more gently too.

-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)