RE: Change of Lisp syntax for "fancy" quotes in Emacs 27?

[Drew Adams <drew.adams@oracle.com>]

> > Helpfulness of error messages surely depends on the beholder, and on
> > expectations.  In my eyes,
> >
> >> Symbol's value as variable is void: 'аbbrevs-changed
> > is quite clear: you think this        ^^^^^^^^^^^^^^^^ is a quoted
> > thing, but the error message calls it a symbol.  So there must be a
> > problem with that quote, it has obviously gotten read as part of the
> > symbol.  Sure, you have still to find out why.
> 
> I think you're making Eli's point, actually :)
> 
> The problem isn't the quote: it's the CYRILLIC SMALL LETTER A instead of
> LATIN SMALL LETTER A.  IOW, (string= "аbbrevs-changed" "abbrevs-
> changed") is nil.
> 
> I think Eli was illustrating the confusion that can stem from Unicode
> confusables (and I must agree that the error message could be much
> better ^^)

I too misread Eli's example as being about using a
curly quote instead of an apostrophe.  You're right
that it's an ordinary apostrophe and the first `a'
is the letter you mention.

But then why would anyone ever see the quote mark
in such a message?  Was the message artificially
configured?

In any case, if that example, without the quote, say,
is trying to make Eli's point, then he must be arguing
for warning about using such confusables also - `а'
as a confusable for `a'.

That's a monumental undertaking (take a look at the
confusables.txt list).  And the messages (warning or
error) would need to be pretty darn clear about just
what char was used and where, in order not to sow
even more confusion.  It sure won't cut the mustard
to just say "Invalid read syntax"!