- Added Functor, Applicative and Monad implementations for Lazy.

1 files changed, 22 insertions, 3 deletions

diff --git a/stdlib/source/lux/data/lazy.lux b/stdlib/source/lux/data/lazy.lux
index 1f4566eee..d2533644a 100644
--- a/stdlib/source/lux/data/lazy.lux
+++ b/stdlib/source/lux/data/lazy.lux
@@ -1,7 +1,9 @@
 (;module:
   lux
   (lux [io]
-       (control monad)
+       (control functor
+                applicative
+                monad)
        (concurrency ["A" atom])
        [macro]
        (macro ["s" syntax #+ syntax:])
@@ -12,8 +14,7 @@
 
   (def: #hidden (freeze' generator)
     (All [a] (-> (-> [] a) (Lazy a)))
-    (let [cache (: (A;Atom (Maybe ($ +0)))
-                   (A;atom #;None))]
+    (let [cache (A;atom (: (Maybe ($ +0)) #;None))]
       (@model (function [_]
                 (case (io;run (A;get cache))
                   (#;Some value)
@@ -32,3 +33,21 @@
   (do @
     [g!_ (macro;gensym "_")]
     (wrap (list (` (freeze' (function [(~ g!_)] (~ expr))))))))
+
+(struct: #export _ (Functor Lazy)
+  (def: (map f fa)
+    (freeze (f (thaw fa)))))
+
+(struct: #export _ (Applicative Lazy)
+  (def: functor Functor<Lazy>)
+
+  (def: (wrap a)
+    (freeze a))
+
+  (def: (apply ff fa)
+    (freeze ((thaw ff) (thaw fa)))))
+
+(struct: #export _ (Monad Lazy)
+  (def: applicative Applicative<Lazy>)
+
+  (def: join thaw))