Newtype ident
diff --git a/src/generics.rs b/src/generics.rs
index a2a66a5..9b60510 100644
--- a/src/generics.rs
+++ b/src/generics.rs
@@ -102,7 +102,7 @@
     named!(pub lifetime<&str, Lifetime>, preceded!(
         punct!("'"),
         map!(word, |ident| Lifetime {
-            ident: format!("'{}", ident),
+            ident: format!("'{}", ident).into(),
         })
     ));