Re: trunk r113818: lisp/xml.el (xml-parse-tag-1): Use looking-at.

[Juanma Barranquero <lekktu@gmail.com>]

On Tue, Aug 13, 2013 at 3:46 AM, Stefan Monnier
<monnier@iro.umontreal.ca> wrote:

> BTW, another thing to learn for this is that we shouldn't bother to
> replace looking-at with looking-at-p.
>
> It can be handy to use looking-at-p if it saves us from using
> save-match-data, but other than that it's not worth the trouble.

I disagree, as I explained before, because I think the greatest
benefit of string-match-p / looking-at-p is that they are predicates.
They're easier to interpret, because you can then forget about ugly
cases like the one which prompted this thread, were the call to the
match-data setting function and its use are quite far apart; that's
error prone, not only to the reader, but to the maintainer that can
easily insert code in between without realizing the mistake.

I don't go out of my way to do the switch, but if I'm fixing other
things or typos or whatever and I find them, and they clearly are used
as predicates, I change them. Every now and them I overlook a use of
match-data, but usually the error is promptly caught.

   J