能否详细说下in的语法

Huu-峰铭顶硬上

#1 Created at ... [Delete] [Delete and Lock User]

两段程序，list内使用整数和字符，结果不一样

第一段 d = {'Michael': 95, 'Bob': 75, 'Tracy': 85} L = ['1','2','3'] E = ['4','5','6'] d ={L[1]:E[1]} print(d) print('%s' % L[1] in d) print('%s' % 2 in d) print('%s' % d.get(2,100)) print('%s' % 'Michael' in d)

返回结果是 {'2': '5'} TRUE TRUE 100 FALSE

符合我的预期

第二段是 d = {'Michael': 95, 'Bob': 75, 'Tracy': 85} L = [1,2,3] E = [4,5,6] d ={L[1]:E[1]} print(d) print('%s' % L[1] in d) print('%s' % 2 in d) print('%s' % d.get(2,100)) print('%s' % 'Michael' in d)

返回结果是 {2: 5} FALSE FALSE 5 FALSE

d已经有了键值2,但是判断返回False,这个让我不解。

Huu-峰铭顶硬上

#2 Created at ... [Delete] [Delete and Lock User]

文中第一段 print('%s' % 2 in d) 实际写得代码是 print('%s' % '2' in d)

是复制错误

廖雪峰

#3 Created at ... [Delete] [Delete and Lock User]

不要把程序搞那么复杂，把自己绕进入了：

>>> d = {2:5}
>>> 2 in d
True

廖雪峰

#4 Created at ... [Delete] [Delete and Lock User]

>>> print('%s' % 2 in d)
False
>>> print('%s' % (2 in d))
True

Huu-峰铭顶硬上

#5 Created at ... [Delete] [Delete and Lock User]

谢谢老师，看完我明白了，是优先级的问题

雨恋小兑

#6 Created at ... [Delete] [Delete and Lock User]

- 把我饶了半天，终于发现是你没加括号才没按你的需求走，刚要回复你发现老师已经回复了很尴尬

阳光曦丶宇风

#7 Created at ... [Delete] [Delete and Lock User]

你好，请问为什么会出现5和100的区别，我的理解错误点在哪里

小丑J2

#8 Created at ... [Delete] [Delete and Lock User]

请问第二段第四行为什么会返回5？

SBSquarePants

#9 Created at ... [Delete] [Delete and Lock User]

d={'2','5'}
print('%s' % 2 in d)

和

d={2,5}
print('%s' % 2 in d)

都返回ture？

SBSquarePants

#10 Created at ... [Delete] [Delete and Lock User]

使用get方法返回值的时候，把2和5当作键值对了，所以当2在（2,5）中式，返回的是5。不在则返回100。

不过这只是我的猜测。

如果是这样的话，是代码不严谨吧

能否详细说下in的语法

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