设计模式-迭代器模式-iterator-python

def

usage

code

from __future__ import print_function

def count_to(count):
"""Counts by word numbers, up to a maximum of five"""
numbers = ["one", "two", "three", "four", "five"]
# enumerate() returns a tuple containing a count (from start which
# defaults to 0) and the values obtained from iterating over sequence
for pos, number in zip(range(count), numbers):
yield number

# Test the generator
count_to_two = lambda: count_to(2)
count_to_five = lambda: count_to(5)

print('Counting to two...')
for number in count_to_two():
print(number, end=' ')

print()

print('Counting to five...')
for number in count_to_five():
print(number, end=' ')

print()

### OUTPUT ###
# Counting to two...
# one two
# Counting to five...
# one two three four five