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From: Terry Reedy <tjreedy@udel.edu>
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Date: Sun, 01 Jul 2012 05:55:24 -0400
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Xref: csiph.com comp.lang.python:24739

On 7/1/2012 2:54 AM, Steven D'Aprano wrote:

> So no, Python has always included chained comparisons, and yes, it is
> shameful that a language would force you to unlearn standard notation in
> favour of a foolish consistency with other operators. Comparisons aren't
> special because they return bools. They are special because of the way
> they are used.
>
> C treats comparison operators as if they were arithmetic operators, and
> so the behaviour of a chained comparison is the same as the behaviour as
> a sequence of arithmetic operators: a foolish consistency. Python treats
> comparison operators as comparison operators, and gives them behaviour
> appropriate to comparisons.

I considered this a great feature of Python when I first learned it. 
Reading about how rare it is among programming languages to treat 
comparisons in the standard way in mathematics reinforces that.

-- 
Terry Jan Reedy