isearch-query-replace-regexp and stuff

[David Kastrup]

As far as I am able to judge from the current code that is just
checked in, if one types M-% from within a regexp isearch or C-M-%
from within an ordinary isearch, the history variable of the last
irrelevant search type gets consulted.

That seems weird.  I think that M-% from within a regexp isearch
should probably use the currently matched string, and C-M-% from
within an ordinary isearch should probably use regexp-quote of the
current search string.

I have no brilliant idea of what to do if we type M-% in a regexp
isearch and there is no currently matched string.  Probably just beep
and refuse, which would also be the sanest option if the regexp is
currently incomplete.  Of course, if query-replace-interactive is
'initial, one might possibly just provide an empty string as initial
value (leaving the history in peace), and if it is nil, we need not
bother anyhow.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum