[Python-Dev] python 3 niggle: None < 1 raises TypeError

Stephen J. Turnbull stephen at xemacs.org
Sat Feb 15 07:03:59 CET 2014

M.-A. Lemburg writes:

 > IMO, it was a mistake to have None return a TypeError in
 > comparisons, since it makes many typical data operations
 > fail, e.g.

I don't understand this statement.  The theory is that they *should*

The example of sort is a good one.  Sometimes you want missing values
to be collected at the beginning of a list, sometimes at the end.
Sometimes you want them treated as top elements, sometimes as bottom.
And sometimes it is a real error for missing values to be present.
Not to mention that sometimes the programmer simply hasn't thought
about the appropriate policy.  I don't think Python should silently
impose a policy in that case, especially given that the programmer may
have experience with any of the above treatments in other contexts.

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