Provide `each` for iteration over collections

[zlikavac32]

Hi,

Thank you for this great library.

One thing that I do miss is having an each method that would just iterate over a collection.

I've seen these three issues:

#51
#50
#49

And was wondering why where they closed and are there any plans for such functionality?

Would a PR for that functionality be an option?

[rtheunissen]

A method like each is the responsibility of an iterator library, ie. function each(iterable $iter): Iterator. There is currently no plan to implement each in 1.x or 2.0