(计算机)Identical vs Equal

Identical (Identity) : "similar in every detail; exactly alike"，可译成 相同。[^1]

equal 的英文解释是 "being the same in quantity, size, degree, or value."，可译成 相等。[^2]

例子

python

python：operator

operator.is_(a, b) Return a is b. Tests object identity

is操作用于判断对象是否相同。

>>> sys.version # python版本
'3.6.9 (default, Apr 18 2020, 01:56:04) \n[GCC 8.4.0]'
>>> a = [1, 2, 3]
>>> b = [1, 2, 3]
>>> a == b # 相等
True
>>> a is b # 不相同
False

Java

在Java语言中，在比较基本类型时==作为"相等"使用[^3]；在比较非基本类型时==作为"相同"使用。[^4]

比较基本类型：

int value1 = 1;
int value2 = 1;
System.out.println(value1 == value2);

比较对象时：

Date a = new Date(123);
Date b = new Date(123);
System.out.println(a==b); //false 不相同
System.out.println(a.equals(b)); //true 相等

参考 References

[^1]: [IDENTICAL | Definition of IDENTICAL by Oxford Dictionary](https://www.lexico.com/definition/identical#:~:text=adjective,in every detail%3B exactly alike.&text='For the final day%2C Torrance,that putt 17 years ago.) [^2]: [equal English Definition and Meaning | Lexico.com](https://www.lexico.com/en/definition/equal#:~:text=adjective,size%2C degree%2C or value.&text='The amount of the deduction,value of the stock contributed.) [^3]: Equality, Relational, and Conditional Operators [^4]: java.util.Date