check if object is number

[Dan Bishop]

Steven Bethard wrote:
> Is there a good way to determine if an object is a numeric type?
> Generally, I avoid type-checks in favor of try/except blocks, but I'm

> not sure what to do in this case:
>
>      def f(i):
>          ...
>          if x < i:
>              ...
>
> The problem is, no error will be thrown if 'i' is, say, a string:
>
> py> 1 < 'a'
> True
> py> 10000000000 < 'a'
> True
>
> But for my code, passing a string is bad, so I'd like to provide an
> appropriate error.
>
> I thought about calling int() on the value, but this will also allow
> some strings (e.g. '1').  I guess this isn't horrible, but it seems
> somewhat suboptimal...

How about this?

... def is_number(x):
...    try:
...       x + 1
...       return True
...    except TypeError:
...       return False