diff --git a/pep-0484.txt b/pep-0484.txt index 1d826eb0e66..df7ab225ac3 100644 --- a/pep-0484.txt +++ b/pep-0484.txt @@ -600,12 +600,10 @@ the type (class) of the objects created by instantiating them doesn't record the distinction. This behavior is called "type erasure"; it is common practice in languages with generics (e.g. Java, TypeScript). -You cannot use the subscripted class (e.g. ``Node[int]``) directly in -an expression -- you must define a type alias. (This restriction -exists because creating the subscripted class, e.g. ``Node[int]``, is -an expensive operation -- usually many times as expensive as -constructing an instance of it. Using a type alias is also more -readable.) +It is not recommended to use the subscripted class (e.g. ``Node[int]``) +directly in an expression -- using a type alias instead is preferred. +(First, creating the subscripted class, e.g. ``Node[int]``, has a runtime +cost. Second, using a type alias is more readable.) Arbitrary generic types as base classes