chickadee » s » s-truncate

If s is longer than len, cut it down and add ... at the end.

(s-truncate 6 "This is too long") ;; => "Thi..."
(s-truncate 16 "This is also too long") ;; => "This is also ..."
(s-truncate 16 "But this is not!") ;; => "But this is not!"