[Python-Dev] Re: switch statement

Jim Jewett jimjjewett at gmail.com
Tue Apr 26 00:20:04 CEST 2005

M.-A. Lemburg wrote:

> Having a simple switch statement
> would enable writing very fast parsers in Python -
> Instead of having one function call per token, you'd
> only have a single dict lookup.

> BTW, has anyone in this thread actually read the PEP 275 ?

I haven't actually seen any use cases outside of parsers 
branching on a constant token.  When I see stacked
elif clauses, the condition almost always includes some 
computation (perhaps only ".startswith" or "in" or a regex 
match), and there are often cases which look at a second 

If speed for a limited number of cases is the only advantage, 
then I would say it belongs in (at most) the implementation, 
rather than the language spec.  


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