bug#31138: Native json slower than json.el

[Eli Zaretskii]

> Cc: sebastien@chapu.is, yyoncho@gmail.com, 31138@debbugs.gnu.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Wed, 24 Apr 2019 23:25:32 +0300
> 
> >> Relying on the library is probably faster.
> > 
> > Why faster?
> 
> Because the library will perform its validation anyway, during normal 
> execution.

But if we validate the string before even calling the library, that
will be even faster, no?

> Any extra validation work Emacs performs, will take time on 
> top of that (of course, I don't know how much time).

Didn't we just establish that it's almost negligible?  Especially for
short strings?

> > And more importantly, will the error indication be useful enough to
> > the Lisp program that triggered it?  If we signal an error, we can
> > make sure of that.
> 
> We still signal errors if the library returns an error code.

But we need to guess the reason.

> Anyway, speeding up encoding is not as important as it was with 
> decoding, because at least in this case Lisp programs can control how 
> much data is sent. So let's not spend too much time and effort on it.

OK.