Deletes a directory.
delete-directory directory &optional error => result
A pathname designator.
delete-directory attempts to delete the directory directory. It returns
t on success, and on failure either returns
nil or signals an error.
error determines what happens when
delete-directory fails. When error is
nil (the default), if directory does not exist
nil, otherwise any failure causes an error to be signaled. If error is
nil on any failure. If error is
:error, any failure causes an error to be signaled.
Typical reasons for failures in
delete-directory are that directory is not empty, or that the user does not have the right permissions.
LispWorks User Guide and Reference Manual - 20 Sep 2017