[Python-Dev] defaultdict proposal round three (original) (raw)

Fuzzyman fuzzyman at voidspace.org.uk
Tue Feb 21 11:17:52 CET 2006

Greg Ewing wrote:

Delaney, Timothy (Tim) wrote:

However, because Python uses duck typing, I tend to feel that subclasses in Python should be drop-in replacements.

Duck-typing means that the only reliable way to assess whether two types are sufficiently compatible for some purpose is to consult the documentation -- you can't just look at the base class list. What's the API for that ?

I've had problems in code that needs to treat strings, lists and dictionaries differently (assigning values to a container where all three need different handling) and telling the difference but allowing duck typing is problematic.

Slightly-off-topic'ly-yours,

Michael Foord

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