迭代器和生成器有什么区别? [英] What is the difference between an Iterator and a Generator?

问题描述

迭代器和生成器有什么区别?

What is the difference between an Iterator and a Generator?

推荐答案

生成器是迭代器，但不是所有的迭代器都是生成器.

Generators are iterators, but not all iterators are generators.

迭代器通常具有 next 方法来从流中获取下一个元素.生成器是与函数绑定的迭代器.

An iterator is typically something that has a next method to get the next element from a stream. A generator is an iterator that is tied to a function.

例如python中的生成器:

For example a generator in python:

def genCountingNumbers():
  n = 0
  while True:
    yield n
    n = n + 1

这样做的好处是您不需要在内存中存储无限的数字来迭代它们.

This has the advantage that you don't need to store infinite numbers in memory to iterate over them.

您可以像使用任何迭代器一样使用它:

You'd use this as you would any iterator:

for i in genCountingNumbers():
  print i
  if i > 20: break  # Avoid infinite loop

你也可以遍历一个数组:

You could also iterate over an array:

for i in ['a', 'b', 'c']:
  print i

这篇关于迭代器和生成器有什么区别?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！