Re: how to control isearch for invisible text

[David Kastrup <dak@gnu.org>]

"Drew Adams" <drew.adams@oracle.com> writes:

>     >     There is no implementation difficulty.  It is not useful
>     >     to search for text that is not part of the visible buffer
>     >     and can't become so without changing its properties.
>     >
>     > You're just repeating here that you don't see the
>     > usefulness. I ask why it wouldn't be useful, and you answer
>     > only "It is not useful."
>
>     You are arguing for an invasive change.  Please describe a
>     concrete actual situation you have encountered where it would
>     actually be useful.  Up to now, you just provided generic
>     handwaving.
>
> OK, so the argument is, after all, that this is not easy to
> implement.

We don't implement things because they are easy.  We implement them
when they are useful.

> I have no "actual situation". I was searching through a buffer that
> had some invisible text (as an overlay), and I wanted to know if
> there was an isearch option for finding it - that's all. You
> answered "yes" - thank you.
>
> I suggested documenting that option better and making it a toggle in
> `isearch'. You said it shouldn't be documented better, it shouldn't
> be a user option after all, and, a fortiori, it shouldn't be toggled
> in `isearch'.

What was it that rendered the text invisible in the first place?  I
know search-invisible since preview-latex has to deal with it
(actually, it is just the XEmacs port, since the Emacs port works with
display properties instead).  The mode was responsible for hiding
stuff away, and consequently it was also responsible for letting them
show up.  Since the behavior of isearch needed fixing, I had to check
in the source file, anyway.  The details were complicated enough that
it would have needed quite long and complicated explanations in the
Elisp manual, for material that would get checked in the code, anyway.

This is my contact with search-invisible.  Now could you please
explain what mode rendered parts of your text invisible so that one
can get an idea whether a global user option makes sense in connection
with that?

> I do hope the user option `search-invisible' 1) remains a user
> option, 2) gets better documented, as it seems useful, and 3) gets
> an associated toggle in `isearch'.

Would you please present an actual example where this would be useful?

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum