From: Robert Klemme <shortcutter@...>
Date: 2010-11-30T23:39:23+09:00
Subject: Re: class-wide begin/end blocks/exception handling

On Tue, Nov 30, 2010 at 1:06 AM, David E. <davidreynon@gmail.com> wrote:
> So I have a class with a lot of methods, and each method has a begin/end
> block
>
> class HiThere
>  def one(stext)
>  begin
>   puts("Hi");
>  rescue Exception => msg
>   self.exceptionHandle(msg)
>  end
>  end
>
>  def two(stext)
>  begin
>   puts("Hi");
>  rescue Exception => msg
>   self.exceptionHandle(msg)
>  end
>  end
>
>  #etc etc
>  #...
> end
>
> ... Is there a way to put one begin/end block encompassing the whole
> class/object? Sort of like an instance-wide begin/end block?

Not directly, but you can do

# needs 1.9
class Proxy < BasicObject
  def initialize(obj)
    @obj = obj
  end

  def method_missing(*a,&b)
    @obj.send(*a,&b)
  rescue ::Exception => e
    handle_exception e
  end

  def handle_exception(e)
    puts e.message
  end
end

irb(main):016:0> s = "foo"
=> "foo"
irb(main):017:0> s + "bar"
=> "foobar"
irb(main):018:0> s + 99
TypeError: can't convert Fixnum into String
        from (irb):18:in `+'
        from (irb):18
        from /opt/bin/irb19:12:in `<main>'
irb(main):019:0> pr = Proxy.new(s)
=> "foo"
irb(main):020:0> pr + "bar"
=> "foobar"
irb(main):021:0> pr + 99
can't convert Fixnum into String
=> nil
irb(main):022:0>

HTH

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/