问题
How would I use a negative form of Python's isinstance()?
Normally negation would work something like
x != 1
if x not in y
if not a
I just haven't seen an example with isinstance(), so I'd like to know if there's a correct way to used negation with isinstance().
回答1:
Just use not
. isinstance
just returns a bool
, which you can not
like any other.
回答2:
That would seem strange, but:
if not isinstance(...):
...
The isinstance
function returns a boolean value. That means that you can negate it (or make any other logical operations like or
or and
).
Example:
>>> a="str"
>>> isinstance(a, str)
True
>>> not isinstance(a, str)
False
回答3:
Just use not
, e.g.,
if not isinstance(someVariable, str):
....
You are simply negating the "truth value" (ie Boolean) that isinstance is returning.
来源:https://stackoverflow.com/questions/11748671/negative-form-of-isinstance-in-python