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Re: Guarding arithmetic

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Date Thu, 23 Aug 2012 19:29:20 +1000
Subject Re: Guarding arithmetic
From Chris Angelico <rosuav@gmail.com>
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On Thu, Aug 23, 2012 at 7:22 PM, Mark Carter <alt.mcarter@gmail.com> wrote:
> OK, so it looks like a solution doesn't exist to the problem as specified. I guess it's something that only a language with macros could accommodate.

You're asking for a function to prevent the evaluation of its
arguments from throwing an error. That's fundamentally not possible
with a function call. Exception handling is a much more normal way of
handling it; though if you prefer, you could wrap it up in a function
like this:

def safe_div(num,denom):
  try:
    return num/denom
  except ZeroDivisionError:
    return 42

print safe_div(1,0)  # still a poor name though

ChrisA

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Thread

Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:05 -0700
  Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-23 19:16 +1000
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:22 -0700
    Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-23 19:29 +1000
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:22 -0700
  Re: Guarding arithmetic Laszlo Nagy <gandalf@shopzeus.com> - 2012-08-23 11:23 +0200
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:47 -0700
    Re: Guarding arithmetic Mark Carter <alt.mcarter@gmail.com> - 2012-08-23 02:47 -0700
  Re: Guarding arithmetic Laszlo Nagy <gandalf@shopzeus.com> - 2012-08-23 11:28 +0200
  Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-23 19:30 +1000
  Re: Guarding arithmetic Peter Otten <__peter__@web.de> - 2012-08-23 12:11 +0200
    Re: Guarding arithmetic rusi <rustompmody@gmail.com> - 2012-08-23 10:15 -0700
  Re: Guarding arithmetic Laszlo Nagy <gandalf@shopzeus.com> - 2012-08-23 13:01 +0200
  Re: Guarding arithmetic MRAB <python@mrabarnett.plus.com> - 2012-08-23 12:21 +0100
  Re: Guarding arithmetic Peter Otten <__peter__@web.de> - 2012-08-23 13:28 +0200
  Re: Guarding arithmetic Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-23 15:11 +0100
  Re: Guarding arithmetic Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-08-23 14:49 -0400
  Re: Guarding arithmetic Chris Angelico <rosuav@gmail.com> - 2012-08-24 07:48 +1000

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