function nonintegerp (was RE: should all floats be nonintegers?)

My nonintegerp function has the defect

  (%i17) featurep(inf,noninteger);
  sign: sign of und is undefined. -- an error. To debug this try: debugmode(true);

I could look for floor to return und, and handle that, but is more general way?

Additionally, should all complex numbers be noninteger? Currently

  (%i1) featurep(%i+7,noninteger);
  (%o1) false

  (%i2) featurep(%i,noninteger);
  (%o2) true


(defun nonintegerp (e)
  (cond ((and (symbolp e) (or (kindp e '$noninteger) (check-noninteger-facts e) (kindp e '$irrational)))) ;declared noninteger
    ((mnump e)
     (if (integerp e) nil t)) ;all floats are noninteger and integers are not nonintegers
    (($ratp e)
     (nonintegerp ($ratdisrep e)))
    (t
     (eq t (mgrp e (take '($floor) e))))))

--Barton