Determining function argument list in Common Lisp

Question

Is it possible to find out the argument list of a function, given a function object (or a function\'s symbol) in common lisp?

Answer 1

I don't know of a standard way but in SBCL you can use sb-introspect:function-lambda-list.

(defun test (a &rest rest &key (b 42)) nil)
(sb-introspect:function-lambda-list #'test)
=> (A &REST REST &KEY (B 42))