>>> x = True
>>> x = not x # toggle
>>> x
False
>>> x = not x # toggle
>>> x
True
>>> x = not x # toggle
>>> x
False
如果值是数字，则从总数中减去是切换值的一种简单快捷的方法：
>>> A = 5
>>> B = 3
>>> total = A + B
>>> x = A
>>> x = total - x # toggle
>>> x
3
>>> x = total - x # toggle
>>> x
5
>>> x = total - x # toggle
>>> x
3
如果值在 0 和 1 之间切换，则可以使用按位异或：
>>> x = 1
>>> x ^= 1
>>> x
0
>>> x ^= 1
>>> x
1
该技术可以推广到任意一对整数。异或一步被替换为预异常数：
>>> A = 205
>>> B = -117
>>> t = A ^ B # precomputed toggle constant
>>> x = A
>>> x ^= t # toggle
>>> x
-117
>>> x ^= t # toggle
>>> x
205
>>> x ^= t # toggle
>>> x
-117
（此想法由Nick Coghlan提交，后来由@zxxc推广。）
如果值是可哈希的，则可以使用字典：
>>> A = 'xyz'
>>> B = 'pdq'
>>> d = {A:B, B:A}
>>> x = A
>>> x = d[x] # toggle
>>> x
'pdq'
>>> x = d[x] # toggle
>>> x
'xyz'
>>> x = d[x] # toggle
>>> x
'pdq'
>>> A = [1,2,3]
>>> B = [4,5,6]
>>> x = A
>>> x = B if x == A else A
>>> x
[4, 5, 6]
>>> x = B if x == A else A
>>> x
[1, 2, 3]
>>> x = B if x == A else A
>>> x
[4, 5, 6]
如果您有两个以上的值，则itertools.cycle（）函数提供了一种通用的快速方法来在连续的值之间进行切换：
>>> import itertools
>>> toggle = itertools.cycle(['red', 'green', 'blue']).next
>>> toggle()
'red'
>>> toggle()
'green'
>>> toggle()
'blue'
>>> toggle()
'red'
>>> toggle()
'green'
>>> toggle()
'blue'
请注意，在Python 3中，next()方法已更改为__next__()，因此第一行现在将写为toggle = itertools.cycle(['red', 'green', 'blue']).__next__
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