Say that lambdas are also allowed as FUNC argument.
;;;###autoload
(defmacro cl-callf (func place &rest args)
"Set PLACE to (FUNC PLACE ARGS...).
-FUNC should be an unquoted function name. PLACE may be a symbol,
-or any generalized variable allowed by `setf'."
+FUNC should be an unquoted function name or a lambda expression.
+PLACE may be a symbol, or any generalized variable allowed by
+`setf'."
(declare (indent 2) (debug (cl-function place &rest form)))
(gv-letplace (getter setter) place
(let* ((rargs (cons getter args)))