test(tests/lean/run): add another IO test

library/system/IO.lean

@@ -3,7 +3,7 @@ Copyright (c) 2016 Microsoft Corporation. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Luke Nelson, Jared Roesch and Leonardo de Moura
 -/
-constant IO : Type → Type₁
+constant IO : Type → Type
 constant functorIO : functor IO
 constant monadIO : monad IO
 

tests/lean/run/IO2.lean

@@ -0,0 +1,13 @@
+import system.IO data.list
+open list
+
+/- B and unit must be in the same universe
+   So, we must put B at Type₁ or use poly_unit
+   since unit is at Type₁
+-/
+
+definition for {A : Type} {B : Type} : list A → (A → IO B) → IO poly_unit
+| []      f := return poly_unit.star
+| (x::xs) f := do f x, for xs f
+
+vm_eval for [1,2,3,4,5] (λ i, do put_str "value: ", put_nat i, put_str "\n")