Persistent Doubly-Linked Lists

(use 'mec.double-list)
;=> nil

(def dl (double-list (range 10)))
;=> #'user/dl

dl
;=> (0 <-> 1 <-> 2 <-> 3 <-> 4 <-> 5 <-> 6 <-> 7 <-> 8 <-> 9)

(remove-tail dl)
;=> (0 <-> 1 <-> 2 <-> 3 <-> 4 <-> 5 <-> 6 <-> 7 <-> 8)

dl
;=> (0 <-> 1 <-> 2 <-> 3 <-> 4 <-> 5 <-> 6 <-> 7 <-> 8 <-> 9)

((juxt seq rseq) dl)
;=> [(0 1 2 3 4 5 6 7 8 9) (9 8 7 6 5 4 3 2 1 0)]

(remove-nth dl 5)
;=> (0 <-> 1 <-> 2 <-> 3 <-> 4 <-> 6 <-> 7 <-> 8 <-> 9)

(add-after *1 (get-nth *1 4) 10)
;=> (0 <-> 1 <-> 2 <-> 3 <-> 4 <-> 10 <-> 6 <-> 7 <-> 8 <-> 9)

(get-head *1)
;=> #:mec.double_list.Node{:prev nil, :next 1, :data 0, :id 0}

(get-next *1)
;=> #:mec.double_list.Node{:prev 0, :next 2, :data 1, :id 1}

(get-prev *1)
;=> #:mec.double_list.Node{:prev 0, :next 2, :data 1, :id 1}