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From: Robert Kern <robert.kern@gmail.com>
Subject: Re: Misleading error message of the day
Date: Thu, 08 Dec 2011 14:47:02 +0000
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:16832

On 12/8/11 2:23 PM, Roy Smith wrote:
> I just spent a while beating my head against this one.
>
> # Python 2.6
>>>> a, b = 'foo'
> Traceback (most recent call last):
>    File "<stdin>", line 1, in<module>
> ValueError: too many values to unpack
>
> The real problem is that there's too *few* values to unpack!  It should
> have been
>
> a, b = 'foo', 'bar'
>
> I understand why it's generating the exception it does (the string is an
> iterable), but man, did that message throw off my thought processes and
> lead me down some totally bogus debugging paths.
>
> It's an unusual case to want to unpack a string.  Maybe the message
> should changed to "too {many, few} values to unpack (are you sure you
> wanted to unpack a string?)" if the RHS is a basestring?

Would including the respective numbers help your thought processes?

ValueError: too many values to unpack (expected 2, got 3)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco