pytypeinfo: rename is_instance to is_type_of

[davidhewitt]

While working on #1276 I realised that PyTypeInfo::is_instance is actually a bit misleading.

The default implementation of it uses PyObject_TypeCheck, which is similar to isinstance() but doesn't call the __isinstance__ hook.

So I think it's better to make this name clearer. I went for check and check_exact, inspired by PyObject_TypeCheck.

This is a little breaking, but I think in practice this should only affect people who are manually implementing PyTypeInfo (hopefully very few users).

[alex]

What do you think about type_check and type_check_exact?

[davidhewitt]

Yeah that's probably even clearer!

[kngwyu]

I understand the motivation, but I still prefer the is_ prefix.

[davidhewitt]

I understand the motivation, but I still prefer the is_ prefix.

I do agree is_ is nicer. I'd really like to move away from is_instance now that I'm aware this is subtly different to the other is_instance functions. Otherwise I think we're asking for people to write bugs by accident!

How about T::is_type_of and T::is_exact_type_of ?

I think that reads quite naturally - e.g. PyList::is_type_of(list) compared to the original PyList::is_instance(list).

[davidhewitt]

Changed to is_type_of and is_exact_type_of. @kngwyu would you be ok with these names?

[kngwyu]

Looks nice 👍