class ref Poperator[T] is Iterator[T^]
Iterate over a [Seq](builtin-Seq.md) descructively by `pop`ing its elements.
Once `has_next()` returns `false`, the [Seq](builtin-Seq.md) is empty.
Nominee for the annual pony class-naming awards.
let _seq: Seq[T]
new create(seq: Seq[T]) =>
_seq = seq
new empty() =>
_seq = Array[T](0)
fun ref has_next(): Bool =>
_seq.size() > 0
fun ref next(): T^ ? =>