Why doesn't Python have switch-case?

Question

Please explain why Python does not have the switch-case feature implemented in it.

Answer 1

Update: There is a new proposal under consideration. See PEP 622 Structural Pattern Matching.

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We considered it at one point, but without having a way to declare named constants, there is no way to generate an efficient jump table. So all we would be left with is syntactic sugar for something we could already do with if-elif-elif-else chains.

See PEP 275 and PEP 3103 for a full discussion.

Roughly the rationale is that the various proposals failed to live up to people's expections about what switch-case would do, and they failed to improve on existing solutions (like dictionary-based dispatch, if-elif-chains, getattr-based dispatch, or old-fashioned polymorphism dispatch to objects with differing implementations for the same method).