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Date: Tue, 5 Feb 2013 16:20:19 +1100
Subject: Re: LBYL vs EAFP
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:38163

On Tue, Feb 5, 2013 at 3:52 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> There's also the principle that it is best to raise an exception as early
> as possible. It's easier to track down errors at the point they are
> introduced than long afterwards.

Yes, definitely, especially (as was mentioned) if you're working with
callbacks. But I'd use isinstance then.

ChrisA