blob: ef9e906b96dfa3316f0b49ee8ef8a1c849008229 (
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
|
; LIB
(record Maybe/Just value)
(record Maybe/Nothing)
(let Maybe/just Maybe/Just/create)
(let Maybe/nothing Maybe/Nothing/create)
(let Maybe/map (\[f m]
(match (kind m)
"Maybe/Just" (Maybe/just (f (Maybe/Just/get-value m)))
"Maybe/Nothing" (Maybe/nothing))))
(let Maybe/and-then (\[f m]
(match (kind m)
"Maybe/Just" (f (Maybe/Just/get-value m))
"Maybe/Nothing" (Maybe/nothing))))
; TESTING
;; (let print-line! (\[s]
;; (print! (concat s "\n"))))
;; (let a (Maybe/just 10))
;; (let b (Maybe/nothing))
;; (Maybe/map (+ 5) a)
;; (Maybe/map (+ 5) b)
;; (Maybe/and-then (\[n] (Maybe/just (+ n 5))) a)
;; (Maybe/and-then (\[n] (Maybe/just (+ n 5))) b)
;; (let m (Maybe/just 10))
;; (match m
;; (Maybe/just _)
;; (print-line! (fmt "found just {0}!" [(Maybe/Just/get-value m)]))
;; (Maybe/nothing)
;; (print-line! "found nothing!"))
;; (let m (Maybe/just 10))
;; (pipe m [
;; (Maybe/map (+ 5))
;; (Maybe/and-then (\[val] (Maybe/just (- val 3))))
;; ])
|
