cons.py

def lazy_any(*args):
	for arg in args:
		if bool(arg()):
			return True
	return False

def is_self_evaluating_term(obj):
	return lazy_any(
		lambda: is_primitive_data(obj),
		lambda: is_primitive_operative(obj),
		lambda: is_symbol(obj),
		lambda: is_ignore(obj));

	
class NilType:
	def __iter__(self):
		raise StopIteration
Nil = NilType()
def is_nil(obj):
	return obj is Nil
	
class cons:
	def __init__(self, left, right):
		self.left = left
		self.right = right
	def __iter__(self):
		yield self.left
		yield from self.right

def make_list(iter):
	return functools.reduce(lambda x, y: cons(y, x), reversed(iter), Nil)

p = cons(1, cons(2, cons(3, Nil)))
for x in p:
	print(x)
q = make_list((1, 2, 3))
for x in q:
	print(x)