27 lines
661 B
Markdown
27 lines
661 B
Markdown
---
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title: Difference between Python 'is' and '==' operators
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localeTitle: Python'是'和'=='运算符之间的区别
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---
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`is`是检查对象标识 - 即检查两个或多个变量是否指向同一个对象。你不能超载`is` 。
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如果变量引用的对象相等，则`==`计算结果为true。您可以通过`__eq__`运算符重载`==` 。
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## 回报价值
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两者的返回值可以是`True`或`False` 。
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## 代码示例
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```
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a = 2.3
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a is 2.3 # => False
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a == 2.3 # => True
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a = [234,123,321]
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b = [234,123,321]
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a == b # => True
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a is b # => False
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a = b
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a == b # => True
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a is b # => True, because if we change a, b changes too
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``` |