Hiding files in dired ?

[David Masterson]

I'm aware of dired-do-kill-lines hiding all marked files in the current
directory buffer.  My question is how to combine the (multiple) marks
and kill into one key.  I suppose I could combine several
dired-mark-files-regexp and the kill into a macro, but I was wondering
if there is something more elegant (flexible?).

Side question: where is the syntax for Emacs regexp documented?
-- 
David Masterson