RE: isearch-allow-move [Was: isearch-allow-prefix]

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

FWIW - I generally agree with what Juri proposes, though I haven't
checked the details.  And I think it does belong in isearch.el, as
much as anything else that is already there.

This kind of thing (performing actions on the fly while searching,
including yanking different things into the search string) greatly
improves Isearch, IMO.  It should be optional and configurable, of
course.

The search string is editable, (even apart from using `M-e'), i.e.,
you can type/delete/yank text there.  And interacting with the search
string is in some ways like interacting with an edit buffer.

But that interaction has long been fairly primitive - there is only
so much you can do.  Letting users take advantage of more of Emacs
for interacting with the search string is a good thing, in general.
This is a move in that direction.  Again, it should be a user choice,
of course.

> 3. Make the value `edit' of the option `search-exit-option' obsolete,
>    i.e. currently when `search-exit-option' is `edit', then typing
>    `C-s C-f C-f C-f' activates the minibuffer and pulls characters
>    to the end of the minibuffer.

That part (description of the current behavior) I do not understand.

The doc string and defcustom indicate that all non-nil values should
behave the same, etc.  What makes a value of `edit' behave differently
from a value of `t' or 42?

Oh, I see that `isearch-other-meta-char' mentions the value `edit',
and treats it specially.

Another bug, apparently: The defcustom and the doc string do not
reflect that possibility at all.  Apparently whoever updated the
function to add this special case did not pay attention to the
definition of the option.