Q about tail recursion

François Pinard pinard at iro.umontreal.ca
Sun Feb 27 09:51:06 EST 2000

Robin Becker <robin at jessikat.demon.co.uk> writes:

> I quite often want to use None as an exceptional return eg in the case of a
> list returning function [] might be a legal return and None an illegal one.

Yes, `None' is a Python natural for a "missing" result, and there are many
cases where such are usefully represented and handled.

> That way I can leave the error handling to the caller. I guess I should
> really be raising an exception though to be truly pythonian.

That might become too heavy (and probably slow), as "missing" is ubiquitous
when handling statistical or experimental data, for example.

François Pinard   http://www.iro.umontreal.ca/~pinard

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