add append method to NEL (#2416)

* add append method to NEL * add doctest for :+
typelevel · Aug 16, 2018 · d4db711 · d4db711
1 parent a2a55b5
commit d4db711
Showing 1 changed file with 16 additions and 0 deletions.
diff --git a/core/src/main/scala/cats/data/NonEmptyList.scala b/core/src/main/scala/cats/data/NonEmptyList.scala
@@ -100,6 +100,22 @@ final case class NonEmptyList[+A](head: A, tail: List[A]) {
   def prepend[AA >: A](a: AA): NonEmptyList[AA] =
     NonEmptyList(a, head :: tail)
 
+  /**
+    * Alias for append
+    *
+    * {{{
+    * scala> import cats.data.NonEmptyList
+    * scala> val nel = NonEmptyList.of(1, 2, 3)
+    * scala> nel :+ 4
+    * res0: cats.data.NonEmptyList[Int] = NonEmptyList(1, 2, 3, 4)
+    * }}}
+    */
+  def :+[AA >: A](a: AA): NonEmptyList[AA] =
+    append(a)
+
+  def append[AA >: A](a: AA): NonEmptyList[AA] =
+    NonEmptyList(head, tail :+ a)
+
   /**
     * Alias for concatNel
     *