General Type Checks (int, str, tuple, etc.)

[Fabian Steiner]

Hello!

So far, I am using something like »if isinstance(var, int):« to
determine, whether var's value is an integer. Now I would like to know
if there is any better possibility to do such general checks or may a
construct with isinstance() even fail in certain cases?

Cheers,
Fabian

[Scott David Daniels]

Re: General Type Checks (int, str, tuple, etc.)

Fabian Steiner wrote:[color=blue]
> Hello!
>
> So far, I am using something like »if isinstance(var, int):« to
> determine, whether var's value is an integer. Now I would like to know
> if there is any better possibility to do such general checks or may a
> construct with isinstance() even fail in certain cases?[/color]

The general rule is: don't check, let it fail if it wants to.
If you are looking for an integral value check, you might prefer:

isinstance(x, (int, long))

but again, think long and hard about your requirements. Embrace
dynamic typing; don't try to write your old language in Python.

--Scott David Daniels
scott.daniels@a cm.org