Re: How to test for native JSON support?

[Eli Zaretskii]

> From: Tim Landscheidt <tim@tim-landscheidt.de>
> Date: Tue, 04 May 2021 11:40:41 +0000
> 
> Nikolay Kudryavtsev <nikolay.kudryavtsev@gmail.com> wrote:
> 
> > json-serialize would return nil if libjansson library is not
> > available during the execution time. So the scenario would
> > be someone building Emacs with json support, then forgetting
> > to put libjansson on his path and/or moving the binary to
> > another machine. Not very likely to happen on any POSIX
> > systems, but a more or less tangible case on Windows.
> 
> That's a rather unexpected, at least undocumented failure
> mode (vulgo: a bug).  IMNSHO in that case json-serialize
> should either "work" or throw an error.

It actually displays an error message, in addition to returning nil
(as do all other JSON primitives in that case).