为什么在Python的双端队列中没有实现__add__？

Question

Concatenating two deque s results in a TypeError .

from collections import deque
q = deque()
q + q

But __iadd__ is implemented so += is supported.

q1 = deque([1])
q2 = deque([2])
q1 += q2

What is the reason that only __iadd__ get implemented?

Answer 1

这是一个已经在repos中修复的bug ，所以它应该包含在下一个发布的Python版本（3.5）中。