From: Robert Cowham <rc@...>
Date: 2003-07-26T08:23:10+09:00
Subject: Re: Add debug to help info

nobu.nokada@softhome.net wrote in news:200307250950.h6P9oUxL026371
@sharui.nakada.kanuma.tochigi.jp:

> Hi,
> 
> At Fri, 25 Jul 2003 18:38:13 +0900,
> Tim Kynerd wrote:
>> I would also be interested to know what the $DEBUG flag does.
> 
> It changes two behaviors.
> 
> Reports exceptions at raised.
> 
>   $ ruby -e 'raise rescue p $!'
>   RuntimeError
> 
>   $ ruby -d -e 'raise rescue p $!'
>   Exception `RuntimeError' at -e:1 -
>   RuntimeError
> 
> Exits main thread when any thread aborted by exceptions.
> 
>   $ ruby -e 'Thread.new{raise};sleep 1'
>   $ ruby -d -e 'Thread.new{raise};sleep 1'
>   Exception `RuntimeError' at -e:1 -
>   -e:1: unhandled exception
>        from -e:1:in `initialize'
>        from -e:1:in `new'
>        from -e:1
> 

That's interesting.

Given the compatibility of Ruby with various Perl flags (-ane for 
example), -d for debug seems more important to me than the above 
behaviour (for the average person....).

Just a thought (and would correspond to least surprise principle too!!)

-- 
Robert Cowham