8.1 Predicates on Numbers

These functions return t if the specified condition is true of the numerical argument, or nil otherwise.

Function: cl-plusp number

This predicate tests whether number is positive. It is an error if the argument is not a number.

Function: cl-minusp number

This predicate tests whether number is negative. It is an error if the argument is not a number.

Function: cl-oddp integer

This predicate tests whether integer is odd. It is an error if the argument is not an integer.

Function: cl-evenp integer

This predicate tests whether integer is even. It is an error if the argument is not an integer.

Function: cl-digit-char-p char radix

Test if char is a digit in the specified radix (default is 10). If it is, return the numerical value of digit char in radix.