[pro] Style issue about predicates

[Nick Levine]

   From: Edi Weitz <edi at weitz.de>
   Date: Fri, 14 Jan 2011 17:59:52 +0100
   Cc: Sergey Vasilyev <sergey at itasoftware.com>,
	   Common Lisp Professionals <pro at common-lisp.net>

   There are lots of functions in the standard which are predicates in
   that they return generalized booleans but on the other hand return
   something "useful" if the result is not NIL, e.g. MEMBER or
   STRING<.  

And some of them might also end in -p

(digit-char-p)

-nick