libcollections: DRY up a PartialEq impl for String

Author: Ryman

src/libcollections/string.rs

@@ -963,15 +963,15 @@ impl PartialEq for String {
 macro_rules! impl_eq {
     ($lhs:ty, $rhs: ty) => {
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl<'a> PartialEq<$rhs> for $lhs {
+        impl<'a, 'b> PartialEq<$rhs> for $lhs {
             #[inline]
             fn eq(&self, other: &$rhs) -> bool { PartialEq::eq(&self[..], &other[..]) }
             #[inline]
             fn ne(&self, other: &$rhs) -> bool { PartialEq::ne(&self[..], &other[..]) }
         }
 
         #[stable(feature = "rust1", since = "1.0.0")]
-        impl<'a> PartialEq<$lhs> for $rhs {
+        impl<'a, 'b> PartialEq<$lhs> for $rhs {
             #[inline]
             fn eq(&self, other: &$lhs) -> bool { PartialEq::eq(&self[..], &other[..]) }
             #[inline]
@@ -984,24 +984,9 @@ macro_rules! impl_eq {
 impl_eq! { String, str }
 impl_eq! { String, &'a str }
 impl_eq! { Cow<'a, str>, str }
+impl_eq! { Cow<'a, str>, &'b str }
 impl_eq! { Cow<'a, str>, String }
 
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b> PartialEq<&'b str> for Cow<'a, str> {
-    #[inline]
-    fn eq(&self, other: &&'b str) -> bool { PartialEq::eq(&self[..], &other[..]) }
-    #[inline]
-    fn ne(&self, other: &&'b str) -> bool { PartialEq::ne(&self[..], &other[..]) }
-}
-
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b> PartialEq<Cow<'a, str>> for &'b str {
-    #[inline]
-    fn eq(&self, other: &Cow<'a, str>) -> bool { PartialEq::eq(&self[..], &other[..]) }
-    #[inline]
-    fn ne(&self, other: &Cow<'a, str>) -> bool { PartialEq::ne(&self[..], &other[..]) }
-}
-
 #[stable(feature = "rust1", since = "1.0.0")]
 impl Default for String {
     #[inline]