Subject: 30.1; Elisp manual: Say what it means for a char to be printable

From: Drew Adams <[email-masked]>
Date: Thu, 27 Feb 2025 17:48:40 +0000

(elisp)`Character Properties' describes variable `printable-chars', but
it doesn't say what "printable" means in this context.  Please add
something about that.

Searching the manual elsewhere, we find only a mention in node `Usual
Display' of "printable ASCII characters" and non-printable ASCII control
characters".

But the printable chars, in general, are not limited to printable ASCII
control chars, so this mention doesn't help with understanding
`printable-chars'.

Please say what's meant by "printable" for `printable-chars'.

[ And I wonder if something shouldn't perhaps be added about (Lisp)
readability in this context.  Some things in Lisp have a print
representation but that can't be read by the Lisp reader.  I believe all
printable chars can be read by the reader.  It wouldn't hurt to mention
this. ]

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