python每日一帖---難懂的現象+清楚的解釋---棘手的字串

標籤：string   false   --   相同   字串   code   aaaaa   aaa   class   

? 字串有時很棘手 *

1.

>>> a = "some_string">>> id(a)140420665652016>>> id("some" + "_" + "string") # 注意兩個id是相同的140420665652016

2.

>>> a = "wtf">>> b = "wtf">>> a is bTrue>>> a = "wtf!">>> b = "wtf!">>> a is bFalse>>> a, b = "wtf!", "wtf!">>> a is bTrue

3.

>>> ‘a‘ * 20 is ‘aaaaaaaaaaaaaaaaaaaa‘True>>> ‘a‘ * 21 is ‘aaaaaaaaaaaaaaaaaaaaa‘False

有道理，對不對？

python每日一帖---難懂的現象+清楚的解釋---棘手的字串