This looks like a good addition feature-wise, but there is quite a bit of duplicated code in it. I think it would be better if we had /one/ implementation based on the iterator protocol, that just uses an additional size hint if len is implemented.

This looks like a good addition feature-wise, but there is quite a bit of duplicated code in it. I think it would be better if we had /one/ implementation based on the iterator protocol, that just uses an additional size hint if len is implemented.

Sure. Presumably sequence protocol => iterator protocol?

It says so in the docs: https://docs.python.org/2/library/stdtypes.html#iterator-types as well as https://docs.python.org/3/library/stdtypes.html#iterator-types:

Sequences [...] always support the iteration methods.

It says so in the docs: https://docs.python.org/2/library/stdtypes.html#iterator-types as well as https://docs.python.org/3/library/stdtypes.html#iterator-types:

Sequences [...] always support the iteration methods.

Ok, have redone - always uses iterator protocol now.

@filmor Passed!

This looks great, thanks :)