Corece to boolean in Common Lisp

Question

Is there a build-in function in Common Lisp to coerce any thing into it's boolean value, like the bool function in Python does?

Answer 1

There's nothing specifically for this. You can't use boolean as the type argument to coerce. You can use:

(defun boolean-value (x)
  (not (not x)))

This is analogous to the !!x idiom used in many other languages.