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+An inherent implementation was defined for a type outside the current crate.
+
+Erroneous code example:
+
+```compile_fail,E0116
+impl Vec<u8> { } // error
+```
+
+You can only define an inherent implementation for a type in the same crate
+where the type was defined. For example, an `impl` block as above is not allowed
+since `Vec` is defined in the standard library.
+
+To fix this problem, you can either:
+
+ - define a trait that has the desired associated functions/types/constants and
+   implement the trait for the type in question
+ - define a new type wrapping the type and define an implementation on the new
+   type
+
+Note that using the `type` keyword does not work here because `type` only
+introduces a type alias:
+
+```compile_fail,E0116
+type Bytes = Vec<u8>;
+
+impl Bytes { } // error, same as above
+```