bug#23010: 25.1.50; Isearch help key to indicate current search state/mode

[Juri Linkov]

>> > This request is for a help key, to show the current state/modes of
>> > Isearch.  The info shown should include all of the possible toggle
>> > states, such as case folding, whitespace folding, regexp/literal, and
>> > char folding, as well as indicate the various toggle keys for these.
>> 
>> I think this sound like it could be vaguely helpful.  I've added Juri
>> to the CCs; perhaps he has some comments.
>> 
>> I think the utility would be pretty marginal, though -- few users alter
>> these things dynamically, but go with one single set of states most of
>> the time.
>
> Why do you think few users do so?  We've added more
> and more such change-state (e.g. toggle) keys over
> time.  And we generally try to indicate the current
> state (e.g. in the mode-line).
>
> If the state were more visible/available then maybe
> more users would "alter these things dynamically"?

So do you suggest something like what query-replace does
where typing `?' displays help about replacements?
Such a buffer could have a different name, e.g.
" *Isearch status*" and display the values
of all togglable options.