Correct way to detect sequence parameter?

Posted by noamtm on Stack Overflow See other posts from Stack Overflow or by noamtm
Published on 2008-11-20T13:52:44Z Indexed on 2010/03/30 20:33 UTC
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python

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types

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sequences

I want to write a function that accepts a parameter which can be either a sequence or a single value. The type of value is str, int, etc., but I don't want it to be restricted to a hardcoded list. In other words, I want to know if the parameter X is a sequence or something I have to convert to a sequence to avoid special-casing later. I could do

type(X) in (list, tuple)

but there may be other sequence types I'm not aware of, and no common base class.

-N.

Edit: See my "answer" below for why most of these answers don't help me. Maybe you have something better to suggest.

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