Re: bug#23750: 25.0.95; bug in url-retrieve or json.el

[Eli Zaretskii]

> From: Philipp Stephani <address@hidden>
> Date: Tue, 29 Nov 2016 23:09:57 +0000
> Cc: address@hidden, address@hidden, address@hidden
> 
>  > json-encode returns a multibyte string.
> 
>  Any idea why? 
> 
> Because (symbol-name 'false) returns a multibyte string. I guess the ultimate 
> reason is that the reader always
> creates multibyte strings for symbol names.

I'm not sure I understand how symbol-name comes into play here.  Can
you help me understand this?

>  Is it again that 'concat' misfeature, when one of the
>  strings is pure-ASCII, but happens to be multibyte?
> 
> Why is it a misfeature?

Because a pure-ASCII string doesn't need to be multibyte, it's only
becomes that by accident.  The net results is that this misfeature
gets in the way when you want to produce a unibyte string by
concatenating an encoded string and some ASCII text.

> I'd expect a concatenation of multibyte and unibyte strings to either 
> implicitly upgrade
> to as multibyte string (as in Python 2) or raise a signal (as in Python 3).

But when all the strings are either unibyte or pure-ASCII, we could
produce a unibyte string without losing anything.