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

[Aaron Ecay]

Hi Noam,

2018ko otsailak 2an, Noam Postavsky-ek idatzi zuen:
> 
> In Emacs 26 and earlier the following is valid lisp code:
> 
> (setq ’bar 42)
> (setq foo ’bar)

I was surprised to learn that this is the case, in light of what is
said in the Elisp reference about symbol names: “A symbol name can
contain any characters whatever. Most symbol names are written with
letters, digits, and the punctuation characters ‘-+=*/’. Such names
require no special punctuation; the characters of the name suffice as
long as the name does not look like a number. (If it does, write a ‘\’
at the beginning of the name to force interpretation as a symbol.) The
characters address@hidden&:<>{}?’  are less often used but also require no
special punctuation. Any other characters may be included in a symbol's
name by escaping them with a backslash.”  (info "(elisp) Symbol Type")

Would it be worth considering making the reader enforce this fully
specification, as an alternative to your patch?  That would solve
this problem with curly quotes in symbol names (which also bit me at
one point), as well as the potential problems with other confusable
characters raised by Paul.

(It might still be desirable to add a special user-friendly error message
when the illegal characters are confusable with an ASCII single quote, as
an additional user-friendliness measure.)

Aaron

PS if this approach is not taken, the manual should at least be changed
to match the actual behavior of the reader.