From: Jeremy Thurgood <jerith@...>
Date: 2008-02-09T16:09:37+09:00
Subject: Re: Timeout::Error

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Joel VanderWerf wrote:
> Jeremy Thurgood wrote:
>> Joel VanderWerf wrote:
>>> Nobuyoshi Nakada wrote:
>>>> Sorry, I can't remember it correctly now.  Perhaps, not to
>>>> happen to be caught accidentally.
>>> That sounds like a good reason:
>> Not to me. I would expect catching StandardError (implicitly or 
>> explicitly) would catch everything I have a reasonable chance of 
>> recovering from, including timeouts. This is my standard strategy when I 
>> am not entirely sure what exceptions may be thrown by third-party code. 
>> There is code in the standard library that throws TimeoutErrors that 
>> need to be caught explicitly:
>>
>>   require 'open-uri'
>>   begin
>>     my_file = open("http://www.example.com/file")
>>   rescue
>>     puts "Sorry, I couldn't open the URL."
>>   end
>>
>> In this case, everything /except/ a timeout will be caught. This is 
>> inconsistent and confusing behaviour to me, especially as it is not 
>> properly documented anywhere that I have seen.
> 
> It not a question of _what_ is recoverable, but _where_ it should be 
> recovered. A timeout should only be caught at a point where it's expected.

And if it's not expected, it should be allowed to crash my application? 
You could make the same statement about any exception, really.

--J

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