RE: `isearch-allow-scroll' - a misnomer and a bad design

[Drew Adams]

>     From this point of view, the whole point of Alan's 
>     changes (and of Drew's suggestion as well) is to *reduce*
>     the modality of isearch.  With Alan's option *on*, scrolling
>     commands now work as they do elsewhere in Emacs: the visible
>     portion of the buffer at hand changes, without disturbing the
>     state of the buffer or the search. 
> 
> I never noticed Alan's proposal, 

Alan's "proposal" wrt scrolling is not a proposal.  It has been part of Emacs
since 2003/2/24, according to a comment in isearch.el.  Blame its admission on
the Emacs maintainer back then, I guess. ;-)

> but now that I see what it is, I am
> against it.  It is very common to use C-v to exit an Isearch.  This
> change would be a painful surprise.

It is a user _option_, and by default the behavior is the one you prefer.
(FWIW, I prefer the same behavior as you for this: `C-v' exits Isearch.)

> The idea that being in a search is a state that commands "shouldn't
> disturb" is the result of thinking of it as a mode.  It is normal
> for editing commands to stop searching and edit instead.

And editing commands are perfectly free to do that.  No one says that commands
"shouldn't disturb" searching.

And commands do so and will continue to do so, even with the new proposal wrt
`C-u'.  Such commands are not bound to keys in `isearch-mode-map', so they will
exit Isearch (and take their `C-u' with them. ;-)).

This is about creating a user _option_ to allow commands that are bound to keys
in `isearch-mode-map' to receive the prefix arg that a user tries to give them.
That's all.

And you have already agreed to adding this option.
What remains to decide is the default value of the option.