Eli Zaretskii <eliz@gnu.org> schrieb am Mi., 30. Nov. 2016 um 17:25 Uhr:

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: Eli Zaretskii <eliz@gnu.org>, p.stephani2@gmail.com, kentaro.nakazawa@nifty.com, emacs-devel@gnu.org
> Date: Wed, 30 Nov 2016 16:48:09 +0100
>
> Yes, this is not a json.el problem at all. It does the correct thing,
> and shouldn't be changed.

??? Why should any code care whether a pure-ASCII string is marked as
unibyte or as multibyte? Both are "correct".

I guess the problem is that process-send-string cares. If it didn't, we wouldn't have the problem.

For URL, we'd need functions like

(byte-array-length s) = (length (string-to-unibyte s))

(process-send-bytes s) = (process-send-string (string-to-unibyte s))

(conceptually; process-send-string also does EOL conversion, which should never be done for HTTP bodies.)