Re: Issue: READ-CASE-SENSITIVITY (Version 2)

[Jeff Dalton <jeff%aiai.edinburgh.ac.uk@NSS.Cs.Ucl.AC.UK>]

I do not understand why this proposal causes such confusion.  Perhaps
my writing isn't as clear as it might be, but I don't think it's that
bad.

> >(2) the lack of need to add CHAR-INVERT-CASE (which I don't think is very 
> >    useful outside of this context).
>  I guess i don't see how this is useful even in this context.
> Is this a Symbolics'ism?

No.

> If :preserve is an option, why would someone want :INVERT?

It's in the rationale.  If I set the readtable to :PRESERVE and
then want to use it to keep case distinctions in my Lisp code --
some people do want to do this -- I may also want to type the names
of symbols in the "LISP" package in lower case rather than upper.
There are two ways to get that: change the internal case to lower
or invert what's typed in.

> dOES SOMEONE THINK :invert IS EASIER TO TYPE THAN eSCAPES or vERTICAL-bARS?
> dO YOU HAVE files WRITTEN WITH :invert?

No, someone thinks (car x) is nicer than (CAR x).

One may well have files written in :INVERT.  Any file that uses only
lower case for Lisp code relies on case-insensitivity to convert the
names to upper case.  Those same files could just as well be read
with :INVERT.

>   [given a sufficiently powerful Emacs that can escape the chars before
>    passing them to the Lisp reader, does any of this matter to X3J13?]

Given sufficiently powerful tools other than Lisp, why does anything
matter to X3J13?

Besides, is Emacs going to read all of my streams for me?

>   While we are busy trying to be KSR33 compatible, the rest of the world
>   may zoom on by.  The Japanese won't be interested in much of this code.
>   Oops, sorry, that is not a cleanup issue.

The only thing in any of this that's could reasonably be called KSR33
compatible is the choice of upper case for the internal preferred
case.  This proposal is trying to make that choice less significant.

-- Jeff