In fact, I proposed adding the ? forms of these functions where the new ones are strictly boolean. These are essential for the SLs since the standard versions are useless due to the true/false tests in the language. <blockquote type="cite">On Nov 11, 2010 6:44 AM, "Jay McCarthy" <<a href="mailto:jay.mccarthy@gmail.com">jay.mccarthy@gmail.com</a>> wrote: I agree with Mark. I often write ? versions of functions like member in my code when I write it the first time to show the "predicate intent". Another important case is when you don't want internal values to "escape" to the client because you forget that member/and/etc return the thing, not #t. Jay On Thu, Nov 11, 2010 at 6:07 AM, Sam Tobin-Hochstadt <<a href="mailto:samth@ccs.neu.edu">samth@ccs.neu.edu</a>> wrote: > On Thu, Nov 11, 2...-- Jay McCarthy <<a href="mailto:jay@cs.byu.edu">jay@cs.byu.edu</a>> Assistant Professor / Brigham Young University <a href="http://faculty.cs.byu.edu/~jay" target="_blank">http://faculty.cs.byu.edu/~jay</a> "The glory of God is Intelligence" - D&C 93 _________________________________________________ For list-related administrative tasks: http://...</blockquote>