I think this will cause more trouble. NewTypes should generally be compared by identity, so creating a new one is problematic. I don't have a better idea though.

I think this will cause more trouble. NewTypes should generally be compared by identity, so creating a new one is problematic. I don't have a better idea though.

@JelleZijlstra I think we can mutate__supertype__ attr ofNewType. So impl will look like this:

ifisinstance(t,NewType):arg=ForwardRef(t.__supertype__)ifisinstance(t.__supertype__,str)elset.__supertype__t.__supertype__=_eval_type(arg,globalns,localns,recursive_guard)returnt

What do you think about such option?

That's also problematic:

1. It's nice to keep all typing objects immutable, since mutable state is the root of much evil.
2. Theglobalns andlocalns in your code sample come from a specific call toget_type_hints. What if I callget_type_hints again later with a different namespace?

Possible solution can be add__eq__ implementation totyping.NewType. But it will go against identity compare.