Writing a string.ishex function

Steve Holden steve at holdenweb.com
Thu Jan 14 18:06:23 CET 2010

chandra wrote:
> On Jan 15, 12:22 am, "D'Arcy J.M. Cain" <da... at druid.net> wrote:
>> Just return False once you find a non-hex digit.
>> def ishex(s):
>>   for c in s:
>>     if not c in string.hexdigits: return False
>>   return True
>> And here are your unit tests.  Every line should print "True".
>> print ishex('123') is True
>> print ishex('abc') is True
>> print ishex('xyz') is False
>> print ishex('0123456789abcdefABCDEF') is True
>> print ishex('0123456789abcdefABCDEFG') is False
> Thanks to Iain and to you.
> One further question: even though it is a single function, is there
> any way to convert it into a module? Can existing modules be enhanced
> with functions such as these? If not, how may I make my own module,
> called, say mystring? At present, I am saving the file as ishex.py and
> calling it after declaring
> from ishex import ishex
> Is there a more elegant way to integrate this function and make it
> available to other python scripts using the import mechanism?
Nope, that's about as elegant as it gets.

You can, of course, include it in a generic utility module and import
several things from that module - you aren't limited to defining a
single object in a module.

Steve Holden           +1 571 484 6266   +1 800 494 3119
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