uiop:split-name-type

(uiop:split-name-type filename)

Two values, the NAME and TYPE of a filename with no directory component: the last dot separates them, except a lone leading dot, which belongs to the name (the type is then uiop:*unspecific-pathname-type*, i.e. nil).

Backend support

Works on all four backends (Lisp source, uiop-pathname.lisp).