separated inner_deref Result impls

Author: Xandkeeper

src/libcore/result.rs

@@ -910,7 +910,7 @@ impl<T: Default, E> Result<T, E> {
 }
 
 #[unstable(feature = "inner_deref", reason = "newly added", issue = "50264")]
-impl<T: Deref, E: Deref> Result<T, E> {
+impl<T: Deref, E> Result<T, E> {
     /// Converts from `&Result<T, E>` to `Result<&T::Target, &E>`.
     ///
     /// Leaves the original Result in-place, creating a new one with a reference
@@ -919,7 +919,10 @@ impl<T: Deref, E: Deref> Result<T, E> {
     pub fn deref_ok(&self) -> Result<&T::Target, &E> {
         self.as_ref().map(|t| t.deref())
     }
+}
 
+#[unstable(feature = "inner_deref", reason = "newly added", issue = "50264")]
+impl<T, E: Deref> Result<T, E> {
     /// Converts from `&Result<T, E>` to `Result<&T, &E::Target>`.
     ///
     /// Leaves the original Result in-place, creating a new one with a reference
@@ -929,7 +932,10 @@ impl<T: Deref, E: Deref> Result<T, E> {
     {
         self.as_ref().map_err(|e| e.deref())
     }
+}
 
+#[unstable(feature = "inner_deref", reason = "newly added", issue = "50264")]
+impl<T: Deref, E: Deref> Result<T, E> {
     /// Converts from `&Result<T, E>` to `Result<&T::Target, &E::Target>`.
     ///
     /// Leaves the original Result in-place, creating a new one with a reference