I updated my track-best library to allow you to keep all of the the things tied for best. The WITH-TRACK-BEST macro now accepts the :KEEP-TIES keyword parameter.
Here are some examples of using the :KEEP-TIES option. For all of the examples, we will use the same sequence of TRACK calls:
(defun track-numbers ()
(track :one 1)
(track :uno 1)
(track :two 2)
(track :dos 2)
(track :one 1)
(track :uno 1)
(track :two 2)
(track :dos 2)
Here are some calls with :KEEP-TIES as NIL (the default):
(with-track-best (:keep 1 :keep-ties nil) (track-numbers))
=> (values :TWO 2)
(with-track-best (:keep 3 :keep-ties nil) (track-numbers))
=> (values (:TWO :DOS :ONE) (2 2 1))
=> (values :TWO 2)
(with-track-best (:keep 3 :keep-ties nil) (track-numbers))
=> (values (:TWO :DOS :ONE) (2 2 1))
Here are some calls with :KEEP-TIES as T:
(with-track-best (:keep 1 :keep-ties t) (track-numbers))
=> (values (:TWO :DOS) (2 2))
(with-track-best (:keep 3 :keep-ties t) (track-numbers))
=> (values (:TWO :DOS :ONE :UNO) (2 2 1 1))
=> (values (:TWO :DOS) (2 2))
(with-track-best (:keep 3 :keep-ties t) (track-numbers))
=> (values (:TWO :DOS :ONE :UNO) (2 2 1 1))