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authorJan Tuomi <jans.tuomi@gmail.com>2022-12-05 14:19:12 +0200
committerJan Tuomi <jans.tuomi@gmail.com>2022-12-05 14:21:53 +0200
commit4002b8988c799a904ef1f359d4267ef4ad80cba3 (patch)
treedbb67560f3a44c57df4b0e960861f60605ceb45f /stdlib/maybe-with-unions.milch
parentbba047ae945ae7d7899d6e2c1610923bcedb0442 (diff)
Rename project to Milch
Diffstat (limited to 'stdlib/maybe-with-unions.milch')
-rw-r--r--stdlib/maybe-with-unions.milch42
1 files changed, 42 insertions, 0 deletions
diff --git a/stdlib/maybe-with-unions.milch b/stdlib/maybe-with-unions.milch
new file mode 100644
index 0000000..53a5024
--- /dev/null
+++ b/stdlib/maybe-with-unions.milch
@@ -0,0 +1,42 @@
+; LIB
+
+(union! Maybe
+ (just value)
+ (nothing))
+
+(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))))
+;; ])