generator sieve of eratosthenes

gensieve.py

"""
A thought that came to me last night in bed.

A generator of erathomous!
"""

class Sieve:
    def __init__(self):
        def series():
            i = 1
            while True:
                i += 1
                yield i
        self.series = series()
        self._generators = set()
        self._nums = set()
        self.primes = set()

    def __iter__(self):
        return self

    def __next__(self):
        # TODO: optimize
        for gen in self._generators:
            next_ = next(gen)
            self._nums.add(next_)
            while next_ < max(self.primes) + 10000:
                next_ = next(gen)
                self._nums.add(next_)

        while True:
            next_ = next(self.series)
            if next_ in self._nums:
                continue
            else:
                self.primes.add(next_)
                self._generators.add(self.get_gen(next_))
                return next_

    def get_gen(self, num):
        def gen(mult):
            cur = mult
            yield cur
            while True:
                cur = mult + cur
                yield cur
        return gen(num)