double equals vs is in python
Question:
I run the following in the Python interpreter:
>>> foo = 10
>>> dir(foo) == dir(10)
True
>>> dir(foo) is dir(10)
False
>>>
Why is this?
Answers:
is checks that 2 arguments refer to the same object, == checks that 2 arguments have the same value. dir() returns a list which contains the same data for both foo and 10, but the actual list instances for the 2 things are different.
I run the following in the Python interpreter:
>>> foo = 10
>>> dir(foo) == dir(10)
True
>>> dir(foo) is dir(10)
False
>>>
Why is this?
is checks that 2 arguments refer to the same object, == checks that 2 arguments have the same value. dir() returns a list which contains the same data for both foo and 10, but the actual list instances for the 2 things are different.