From: Robert Klemme <shortcutter@...>
Date: 2010-03-24T06:45:28+09:00
Subject: Re: what's the suggested raise Exception idiom?

On 03/23/2010 06:22 PM, Nathan Beyer wrote:
> What's the distinction between:
>    raise ArgumentError, "the argument was invalid"
> and
>   raise ArgumentError.new("the argument was invalid")
> 
> How does this apply in the case of exceptions with custom initializers
> for attributes? For example:
>   class StatusCodeError < StandardError
>       attr_reader :status_code
>       def initialize(status_code)
>           @status_code = status_code
>       end
>   end
> 
> I've been reading a lot of code, books and blogs, but haven't gotten
> as clear of an understanding on why people choose one way over
> another, so I'm looking for additional opinions and commentary.

I believe raise a,b,c,d... is merely syntactig sugar for raise 
a.new(b,c,d...) with a bit of added functionality (e.g. if a is not an 
exception class there is an error, if a is a String a StandardError is 
raised).

To answer your question, normally there is no reason to use a variant 
with "new" - rather save yourself a bit of typing and use the shorter 
form.  My 0.02EUR.

Kind regards

	robert

-- 
remember.guy do |as, often| as.you_can - without end
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