RE: search-invisible and friends

[Drew Adams <drew.adams@oracle.com>]

> >> If not, I think it should, and perhaps (or perhaps not?) by
> >> piggy-backing on the search-invisible variable.
> >
> > How about extending search-invisible to support additional properties,
> > by providing some variable that would hold the list of such
> > properties?  Then we could also avoid searching in text that is
> > visible, if some Lisp needs that (for example, you could have a form
> > where you'd like to search only the writable fields).
> 
> Ah, yeah, that sounds quite useful and natural.

I too support the general idea.  But I do hope that
the existing code interface for search-invisible
continues to work as is.  IOW, can we add such a
feature without breaking existing code?

> We could even have a
> standard property like `no-search' that could be part of the default
> `search-invisible' value, so that modes can easily mark out regions that
> shouldn't be searched for.  In which case, the whole `display' thing
> becomes moot -- in my mode, I could just slap the `no-search' property
> on all the image display bits that I want isearch to avoid?

It may not be just what you're asking for there, but
my code (libraries `zones.el' and `isearch-prop.el')
lets you easily toggle zones of text between visible
and visible (which affects search as expected).

It also lets you toggle visibility of the anti-zones,
i.e., the complement of a set of zones.

And you can limit isearch to being inside or outside
a set of zones.  (This includes the simple case of
limiting search to the region - inside or outside it.)

And you can interactively define zones by the presence
of text properties (including with particular values).
And you can interactively put properties on the text
in a set of zones, or add properties to areas of text
that have other given properties and property values.

And you can narrow the zones to search to those with
lazy-highlighting.  Which means you can search for one
thing, and then refine the search by searching for
something else within those search hits.
____


Zones description:
https://www.emacswiki.org/emacs/Zones

zones.el:
https://www.emacswiki.org/emacs/download/zones.el

Isearch Properties:
https://www.emacswiki.org/emacs/IsearchPlus

isearch-prop.el:
https://www.emacswiki.org/emacs/download/isearch-prop.el