def filter(self):
l = LazyList(range(30))
l2 = l.filter(_ % 2 == 0)
l2.strict.should.have.length_of(0)
l3 = LazyList(range(30))
l3[29]
l4 = l3.filter(_ % 2 == 0)
l4.strict.should.have.length_of(15)
l4.drain.should.equal(List.wrap(range(0, 30, 2)))
def traverse(self):
n = 3
l = LazyList(map(Just, range(n)))
target = LazyList(List.wrap(range(n)))
(l.sequence(Maybe) / _.drain).should.contain(target.drain)
def deep(self):
n = int(1e4)
l = LazyList(List.wrap(range(n)))
l.index_of(n - 1).should.contain(n - 1)
def find(self):
l = LazyList(range(30), chunk_size=20)
l.find(_ == 21).should.contain(21)
l.find(_ == 49).should.be.empty
def index_of(self):
l = LazyList(range(30), chunk_size=20)
l.index_of(21).should.contain(21)
l.index_of(49).should.be.empty
def with_index(self):
l = LazyList(itertools.count(), chunk_size=20)
l2 = l.map(_ * 5).with_index
l2[:2].should.equal(List((0, 0), (1, 5)))
def map(self):
l = LazyList(itertools.count(), chunk_size=20)
l2 = l.map(_ * 10)
l2[:5].should.equal(List.wrap(range(0, 50, 10)))
