`list`, `tuple`, `set`, `frozenset` and `dict` with or without `*` work by indexing or slicing which is problematic

[hyperkai]

Bug report

Bug description:

list, tuple, set, frozenset and dict with or without * work by indexing or slicing as shown below so these below are problematic so they should return error:

print(list[10])      # list[10]
print(tuple[10])     # tuple[10]
print(set[10])       # set[10]
print(frozenset[10]) # frozenset[10]
print(dict[10])      # dict[10]

print(*list[10])      # *list[10]
print(*tuple[10])     # *tuple[10]
print(*set[10])       # *set[10]
print(*frozenset[10]) # *frozenset[10]
print(*dict[10])      # *dict[10]

print(list[0:10:3])      # list[slice(0, 10, 3)]
print(tuple[0:10:3])     # tuple[slice(0, 10, 3)]
print(set[0:10:3])       # set[slice(0, 10, 3)]
print(frozenset[0:10:3]) # frozenset[slice(0, 10, 3)]
print(dict[0:10:3])      # dict[slice(0, 10, 3)]

print(*list[0:10:3])      # *list[slice(0, 10, 3)]
print(*tuple[0:10:3])     # *tuple[slice(0, 10, 3)]
print(*set[0:10:3])       # *set[slice(0, 10, 3)]
print(*frozenset[0:10:3]) # *frozenset[slice(0, 10, 3)]
print(*dict[0:10:3])      # *dict[slice(0, 10, 3)]

CPython versions tested on:

3.12

Operating systems tested on:

Windows

[picnixz]

print can show an arbitrary number of values; what is the issue here?

[sergey-miryanov]

dict and set don't support slicing. it is not clear what do you expect in such cases.

[JelleZijlstra]

This is using typing syntax (PEP-585, PEP-646). These are not legal in the type system but the runtime does not (and should not) check for valid types.

[George-Ogden]

You are printing type hints. These types are generic (https://docs.python.org/3/library/typing.html#generic). Usually, you would use list[int] or dict[str, Any] for type hints. The star notation (https://docs.python.org/3/library/typing.html#typing.Unpack) is used to represent the unpacked type, which is more common in tuples.