(defknown get-output-stream-string (stream) simple-string ())
(defknown streamp (t) boolean (movable foldable flushable))
(defknown stream-element-type (stream) type-specifier
(defknown get-output-stream-string (stream) simple-string ())
(defknown streamp (t) boolean (movable foldable flushable))
(defknown stream-element-type (stream) type-specifier