How can I tell if variable is defined

Dave Angel davea at ieee.org
Tue Sep 22 22:16:45 CEST 2009


Brown, Rodrick wrote:
> How could I do the following check in Python
>
> In Perl I could do something like if ((defined($a)) { ... }
>
> I tried if var is not None:
> However this doesn't seem to work as described.
>
> Thanks.
>
>
>   
try/except

Or look up the attribute in the appropriate dictionary(ies).


def test():
    newvar = 42
    if "newvar" in locals():
        print "yes"

DaveA




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