diff --git a/src/func/context.rs b/src/func/context.rs
index f3e69c4..f3f58f0 100644
--- a/src/func/context.rs
+++ b/src/func/context.rs
@@ -1,21 +1,20 @@
 use super::*;
 
+pub type WrapC<'a, A, Ctx> = Wrap<'a, A, <Ctx as FunctorContext<'a>>::T>;
+
 pub trait FunctorContext<'a>: 'a {
     type T: WeakFunctor<'a>;
 }
 
 pub trait FunctorContextExt<'a>: FunctorContext<'a> {
-    fn fmap<A: 'a, B: 'a>(
-        fa: Wrap<'a, A, Self::T>,
-        f: impl 'a + FnOnce(A) -> B,
-    ) -> Wrap<'a, B, Self::T>
+    fn fmap<A: 'a, B: 'a>(fa: WrapC<'a, A, Self>, f: impl 'a + FnOnce(A) -> B) -> WrapC<'a, B, Self>
     where
         Self::T: Functor<'a>,
     {
         <Self::T as Functor>::fmap(fa, f)
     }
 
-    fn pure<A: 'a>(a: A) -> Wrap<'a, A, Self::T>
+    fn pure<A: 'a>(a: A) -> WrapC<'a, A, Self>
     where
         Self::T: Pure<'a>,
     {
@@ -23,16 +22,16 @@ pub trait FunctorContextExt<'a>: FunctorContext<'a> {
     }
 
     fn bind<A: 'a, B: 'a>(
-        fa: Wrap<'a, A, Self::T>,
-        f: impl 'a + FnOnce(A) -> Wrap<'a, B, Self::T>,
-    ) -> Wrap<'a, B, Self::T>
+        fa: WrapC<'a, A, Self>,
+        f: impl 'a + FnOnce(A) -> WrapC<'a, B, Self>,
+    ) -> WrapC<'a, B, Self>
     where
         Self::T: Monad<'a>,
     {
         <Self::T as Monad>::bind(fa, f)
     }
 
-    fn fail<A: 'a, E: 'a>(e: E) -> Wrap<'a, A, Self::T>
+    fn fail<A: 'a, E: 'a>(e: E) -> WrapC<'a, A, Self>
     where
         Self::T: Fail<'a, E>,
     {