lispdoc - results for zerop

(zerop number)
Function: Is this number zero?
Example:
(defun empty-p (playlist)
  (zerop (table-size (songs-table playlist))))
Mentioned in:
CLtL2 - 12.2. Predicates on Numbers
HyperSpec - Function ZEROP
On Lisp - Local Functions
PCL - numeric comparisons
Successful Lisp - chapter04
Successful Lisp - chapter22
Successful Lisp - tail recursion