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Date: Fri, 31 Jan 2014 00:55:44 +1100
Subject: Re: 1 > 0 == True -> False
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:65002

On Fri, Jan 31, 2014 at 12:40 AM, Thibault Langlois
<thibault.langlois@gmail.com> wrote:
> The recommendations to student are 1) do not assume True == 1 and do not use operator chaining.

Not "do not use", but "do not misuse". Python's operator chaining is
awesome for bounds checking:

if 3 < x < 20:
  print("x is between 3 and 20, exclusive")

You can even, since it short-circuits, do crazy stuff like:

x = random.randrange(30)
if int(input("Min: ")) < x < int(input("Max: ")):
    print("It's within those bounds.")

It won't ask for a maximum if it's already failed to be within the
minimum. (Okay, don't do this one. Not good code. Heh.)

But don't use operator chaining when you don't mean it to behave that
way. That's all!

ChrisA