Polish: add Array.empty

gcanti · Sep 24, 2018 · cbbbe2f · cbbbe2f
1 parent 61f301f
commit cbbbe2f
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Showing 2 changed files with 26 additions and 2 deletions.
diff --git a/docs/Array.md b/docs/Array.md
@@ -7,6 +7,22 @@ title: Module Array
 
 ## Constants
 
+### empty
+
+_constant_
+
+_since 1.9.0_
+
+_Signature_
+
+```ts
+empty: Array<never>
+```
+
+_Description_
+
+An empty array
+
 ### getSetoid
 
 _constant_

diff --git a/src/Array.ts b/src/Array.ts
@@ -47,7 +47,7 @@ export type URI = typeof URI
 export const getMonoid = <A = never>(): Monoid<Array<A>> => {
   return {
     concat,
-    empty: []
+    empty
   }
 }
 
@@ -160,7 +160,15 @@ export function traverse<F>(F: Applicative<F>): <A, B>(ta: Array<A>, f: (a: A) =
   return (ta, f) => reduce(ta, F.of(zero()), (fab, a) => liftedSnoc(fab)(f(a)))
 }
 
-const zero = <A>(): Array<A> => []
+/**
+ * An empty array
+ *
+ * @constant
+ * @since 1.9.0
+ */
+export const empty: Array<never> = []
+
+const zero = <A>(): Array<A> => empty
 
 const alt = concat