如何从Python中的生成器获取一个值?

Very basic question - how to get one value from a generator in Python?

非常基本的问题——如何从Python中的生成器获取一个值?

So far I found I can get one by writing gen.next(). I just want to make sure this is the right way?

到目前为止，我发现我可以通过写gen.next()得到一个。我只是想确定这是正确的方法?

5 个解决方案

#1

Yes, or next(gen) in 2.6+.

是的，或者是2.6+的下一代(gen)。

#2

In Python <= 2.5, use gen.next(). This will work for all Python 2.x versions, but not Python 3.x

在Python <= 2.5中，使用gen.next()。这将适用于所有Python 2。x版本，但不是Python 3.x

In Python >= 2.6, use next(gen). This is a built in function, and is clearer. It will also work in Python 3.

在Python >= 2.6中，使用next(gen)。这是一个内置的函数，而且更清晰。它也将在Python 3中工作。

Both of these end up calling a specially named function, next(), which can be overridden by subclassing. In Python 3, however, this function has been renamed to __next__(), to be consistent with other special functions.

这两个函数最后都调用了一个特殊命名的函数next()，这个函数可以通过子类化来重写。然而，在Python 3中，这个函数被重命名为__next__()，以与其他特殊函数保持一致。

#3

This is the correct way to do it.

这是正确的方法。

You can also use next(gen).

您还可以使用next(gen)。

http://docs.python.org/library/functions.html#next

http://docs.python.org/library/functions.html下

#4

In python 3 you don't have gen.next(), but you still can use next(gen). A bit bizarre if you ask me but that's how it is.

在python 3中没有gen.next()，但是仍然可以使用next(gen)。如果你问我，这有点奇怪，但事实就是如此。

#5

Use (for python 3)

使用python(3)

next(generator)

Here is an example

这是一个例子

def fun(x):
    n = 0
    while n < x:
        yield n
        n += 1
z = fun(10)
next(z)
next(z)

should print

应该打印

0
1

#1