Enforce E0719 only for trait aliases

1 files changed, 4 insertions, 10 deletions

diff --git a/compiler/rustc_error_codes/src/error_codes/E0719.md b/compiler/rustc_error_codes/src/error_codes/E0719.md
index cd981db1058..17cbd2de49e 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0719.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0719.md
@@ -1,4 +1,4 @@
-An associated type value was specified more than once.
+An associated item value was specified more than once in a trait object.
 
 Erroneous code example:
 
@@ -7,21 +7,15 @@ trait FooTrait {}
 trait BarTrait {}
 
 // error: associated type `Item` in trait `Iterator` is specified twice
-struct Foo<T: Iterator<Item: FooTrait, Item: BarTrait>> { f: T }
+type Foo = dyn Iterator<Item = u32, Item = u32>;
 ```
 
-`Item` in trait `Iterator` cannot be specified multiple times for struct `Foo`.
-To fix this, create a new trait that is a combination of the desired traits and
-specify the associated type with the new trait.
+To fix this, remove the duplicate specifier:
 
 Corrected example:
 
 ```
-trait FooTrait {}
-trait BarTrait {}
-trait FooBarTrait: FooTrait + BarTrait {}
-
-struct Foo<T: Iterator<Item: FooBarTrait>> { f: T } // ok!
+type Foo = dyn Iterator<Item = u32>; // ok!
 ```
 
 For more information about associated types, see [the book][bk-at]. For more