字典的pop()的非破坏性版本 [英] non-destructive version of pop() for a dictionary

问题描述

有没有从字典中获取任意键，值对而不删除它们的习惯用法?(P3K)

Is there any idiom for getting an arbitrary key, value pair from a dictionary without removing them? (P3K)

对不起，措辞混乱.

我用任意这个词的意思是我不在乎得到的东西.

I used the word arbitrary in the sense that I don't care about what I'm getting.

它不同于随机的，我在乎我得到的东西(即，我需要选择每个项目的概率是相同的).

It's different from random, where I do care about what I'm getting (i.e., I need probabilities of each item being chosen to be the same).

而且我没有可使用的钥匙.如果这样做的话，我认为它将属于RTFM类别，因此不应该在SO上给出答案.

And I don't have a key to use; if I did, I'd think it would be in the RTFM category and wouldn't deserve an answer on SO.

不幸的是，在P3K中， .items()返回一个 dict_items 对象，与Python 2不同，它返回了一个迭代器:

Unfortunately in P3K, .items() returns a dict_items object, unlike Python 2 which returned an iterator:

ActivePython 3.1.2.4 (ActiveState Software Inc.) based on
Python 3.1.2 (r312:79147, Sep 14 2010, 22:00:46) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> d = {1:2}
>>> k,v = next(d.items())
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: dict_items object is not an iterator

推荐答案

k, v = next(iter(d.items())) # updated for Python 3

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