diff --git a/src/dist/inductive/list.jl b/src/dist/inductive/list.jl
index 4b32db8d..36b48d66 100644
--- a/src/dist/inductive/list.jl
+++ b/src/dist/inductive/list.jl
@@ -31,9 +31,9 @@ end
 
 function one_of(l::List{T})::Opt.T{T} where T <: Dist
     match(l, [
-        :Nil => () -> Opt.None(T),
+        :Nil => () -> Opt.OptNone(T),
         :Cons => (x, xs) -> @alea_ite if flip_reciprocal(length(l))
-            Opt.Some(T, x)
+            Opt.OptSome(T, x)
         else
             one_of(xs)
         end
diff --git a/src/dist/inductive/option.jl b/src/dist/inductive/option.jl
index 38ce15f8..aaea36e0 100644
--- a/src/dist/inductive/option.jl
+++ b/src/dist/inductive/option.jl
@@ -3,21 +3,19 @@ export Opt
 
 module Opt
     using Alea
-    @type T{A} = None() | Some(A)
-
-    Some(x) = Some(typeof(x), x)
+    @type T{A} = OptNone() | OptSome(A)
 
     function bind(f, T, x::Opt.T)
         @match x [
-            None() -> None(T),
-            Some(x) -> f(x)
+            OptNone() -> OptNone(T),
+            OptSome(x) -> f(x)
         ]
     end
 
     function map(f, T, x::Opt.T)
         @match x [
-            None() -> None(T),
-            Some(x) -> Some(T, f(x))
+            OptNone() -> OptNone(T),
+            OptSome(x) -> OptSome(T, f(x))
         ]
     end
 end