diff --git a/src/func/applicative_select.rs b/src/func/applicative_select.rs
index 98beced..bdaf72d 100644
--- a/src/func/applicative_select.rs
+++ b/src/func/applicative_select.rs
@@ -19,17 +19,14 @@ pub trait ApplicativeSelect: Functor {
     }
 }
 
-pub trait ApplicativeSelectExt: ApplicativeSelect {
-    fn select_map<'a, A: 'a, B: 'a, C: 'a>(
+pub trait ApplicativeSelectExt<'a>: 'a + ApplicativeSelect {
+    fn select_map<A: 'a, B: 'a, C: 'a>(
         f: impl 'a + FnOnce(Selected<'a, A, B, Self>) -> C,
         fa: Self::F<'a, A>,
         fb: Self::F<'a, B>,
-    ) -> Self::F<'a, C>
-    where
-        Self: 'a,
-    {
+    ) -> Self::F<'a, C> {
         Self::fmap(f, Self::select(fa, fb))
     }
 }
 
-impl<T: ApplicativeSelect> ApplicativeSelectExt for T {}
+impl<'a, T: 'a + ApplicativeSelect> ApplicativeSelectExt<'a> for T {}