Added lexars

lexers/testdata/gleam.actual

@@ -0,0 +1,20 @@
+import gleam/io
+
+@external(erlang, "lists", "reverse")
+pub fn reverse_list(items: List(e)) -> List(e) {
+  tail_recursive_reverse(items, [])
+}
+
+/// Tail recursion!
+fn tail_recursive_reverse(items: List(e), reversed: List(e)) -> List(e) {
+  case items {
+    [] -> reversed
+    [first, ..rest] -> tail_recursive_reverse(rest, [first, ..reversed])
+  }
+}
+
+pub fn main() {
+	let _thing = <<"Hello, Joe!":utf8>>
+  io.debug(reverse_list([1, 2, 3, 4, 5]))
+  io.debug(reverse_list(["a", "b", "c", "d", "e"]))
+}