From: Brian Candler <B.Candler@...>
Date: 2003-08-14T00:09:17+09:00
Subject: Exception reporting change?

There appears to have been a change in exception handling in ruby-1.8. In
1.6.8 I was able to create an object containing detailled information about
the exception for the benefit of the receiver, and pass it in the 'message'
field:

------------------------------------------------------------------------
class Code
  def initialize(code, text)
    @code = code
    @text = text
  end
  def to_s
    "#{@text} (#{@code})"
  end
  def to_str
    @text
  end
end

begin
  raise StandardError, Code.new(550, "Relaying Denied")
rescue Exception => e
  p $!.class
  p $!.message.class
  puts "Error: #{$!}"
  puts "Error: #{$!.message}"
end
------------------------------------------------------------------------

Under 1.6.8 this gives:

StandardError
Code
Error: #<StandardError:0x8102ac4>
Error: Relaying Denied (550)

But under 1.8.0 I get:

StandardError
String
Error: Relaying Denied
Error: Relaying Denied

It appears that my information object has been flattened into a string
before the exception itself is raised.

Was this intentional? If so, what should I do now? Would it be better to
embed my information directly in an exception object:

  class MyException < StandardError
    def initialize(code, text)
      @code = code
      @text = text
    end
  end
  ...
  raise MyException.new(550,"Relaying Denied")

I have this sort of thing all over my code, so I want to know the official
supported way of doing this before I start changing it all :-)

Thanks...

Brian.