Map to -> return.

src/libcore/any.rs

@@ -448,7 +448,7 @@ impl TypeId {
 /// This is intended for diagnostic use. The exact contents and format of the
 /// string returned are not specified, other than being a best-effort
 /// description of the type. For example, amongst the strings
-/// that `type_name::<Option<String>>()` might map to are `"Option<String>"` and
+/// that `type_name::<Option<String>>()` might return are `"Option<String>"` and
 /// `"std::option::Option<std::string::String>"`.
 ///
 /// The returned string must not be considered to be a unique identifier of a