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From: Gregory Ewing <greg.ewing@canterbury.ac.nz>
Newsgroups: comp.lang.python
Subject: Re: Functional programming
Date: Tue, 04 Mar 2014 11:06:31 +1300
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Xref: csiph.com comp.lang.python:67594

Steven D'Aprano wrote:
> Given that x is an integer, and that you add 1 (also an integer) to it, 
> is it really necessary to tell the compiler that add_one returns an 
> integer? What else could the output type be?

Just because the compiler *can* infer the return type
doesn't necessarily mean it *should*. When I was playing
around with functional languages, I ended up adopting the
practice of always declaring the types of my functions,
because it helps the *human* reader. (It also helped the
compiler produce comprehensible error messages in the
event of a type error.)

-- 
Greg