Re: new apropos feature in Emacs-22

[Eli Zaretskii]

> Date: Sat, 5 Nov 2005 23:36:17 -0600 (CST)
> From: Luc Teirlinck <address@hidden>
> CC: address@hidden
> 
> Eli Zaretskii wrote:
> 
>    Whether newbies are accustomed to this remains to be proven, but the
>    characters ``natural in the Emacs context'' above come from an
>    experienced user.
> 
> .emacs and *scratch* are only for experienced users?

You were talking about `.', `+', and `*' in general.

And yes, at least *scratch* is not something an unexperienced user
will look for, I think.

>    > In the keyword searches that I am familiar with you can enclose the
>    > keywords in quotation marks to force sequential in order occurrence.
> 
>    That's an advanced feature, you know.
> 
> Really?  I always use quotation marks in websearches

Then in my experience, you are a minority.

> and would not know how to search without them.

Just lose the quotes, it works ;-)

> For instance, Richard asked us for a
> string that gave him all postings in the old thread we are talking
> about and nothing else and I said:
> 
> "apropos commands and regexps" (_with_ the quotation marks included).
> 
> It works.

It could also misfire, e.g., if the actual phrase in the archives is
"regexps and apropos commands".  If you lose the quotes (and "and" as
well), you will find it regardless of the order.

In general, quotes are useful only if you know _exactly_ how the
phrase appears in the text, which is a relatively rare situation.
(I'm sure you know all this already.)

>    > I believe that after your change, newbies _still_ will have to learn
>    > about regexps to accomplish what they are used to in search engines.
> 
>    Please explain why you think so.
> 
> Several reasons.
> 
> Because you may want to search for, say, the words "overwrite mode" in
> that order, separated only by non-word constituents.

That's your ``always use quotes'' rule again; see above for why it
might not be useful for someone (like a newbie) who does not know the
exact phrase she is looking for.

> The fact that "mode" occurs somewhere in a doc string and
> "overwrite" somewhere else is usually completely irrelevant and
> produces many false hits.

False hits is a downside of any search engine (including `apropos' in
its pre-Emacs22 incarnation, btw).  Scoring and sorting according to
score--a new feature introduced together with the one we are
discussing--are supposed to alleviate that.

> Sequential occurrence is _much_ less likely to be an accident

Yes, _if_ you know the exact phrase.  A rather big IF, I'd say.
Mostly false for newbies, in my experience.

> _And_ because sometimes you might want to search for keywords
> containing characters that happen to be special in regexps, say
> .emacs, .mailrc, whatever.

A regexp ".emacs" will find a literal ".emacs", so this is not a big
problem.