summaryrefslogtreecommitdiff
path: root/lib/array.fnl
blob: 9ed0d806e07a0c87b3e727cda6187117bb6f14fd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
(import-macros {: reduce} :lib.macro)

(fn concat [a b]
  (local copy
   (fn [a b]
     (reduce
      (fn [_ v res]
       (table.insert res v)
       res)
      b a)))
  (copy a b))

(fn flip [a]
  (collect [k v (pairs a)]
    (values v k)))

(fn diff [a b]
  (local flip-b (flip b))
  (reduce
    (fn [_ v res]
      (when (not (. flip-b v))
        (table.insert res v))
      res)
    a []))

(fn unique [a]
  (var hash {})
  (reduce
    (fn [_ v res]
      (when (not (. hash v))
        (tset hash v true)
        (table.insert res v))
      res)
    a []))

(fn flatten [a]
 (reduce
  (fn [_ value rest]
    (concat
      rest
      (if (= (type value) "table")
        (flatten value)
        [value])))
  a []))

(local join table.concat)

{: concat : diff : unique : flatten : join}