From: Jacob Fugal <lukfugl@...>
Date: 2005-12-23T03:40:08+09:00
Subject: Re: String > Integer Conversion Problem

On 12/22/05, dblack@wobblini.net <dblack@wobblini.net> wrote:
> On Fri, 23 Dec 2005, Joel VanderWerf wrote:
> > This has the unfortunate side effect of conflating NoMethodErrors that
> > are reported for other method calls besides the original obj.meth but
> > which occur during that method. What's the best way of handling that?
> > Compare exception.backtrace depth with the current backtrace depth?
>
> I guess, but it gets awfully cluttered.  I don't know what the best
> way is.  Too bad exceptions don't have a depth property or
> something....

How about something like this:

  class Exception
    def self.local
      primary = self
      localized = Class.new
      klass = (class << localized; self; end)
      klass.send(:define_method, :===) do |other|
        primary === other and other.depth == 1
      end
      localized
    end

    def depth
      self.backtrace.length
    end
  end

Usage:

  begin
    bar()
  rescue NoMethodError.local => e
  end

  def bar
    foo()
  end

  begin
    bar()
  rescue NoMethodError.local => e
  end

First rescue catches the undefined bar since it's local, second rescue
doesn't catch the undefined foo since it's not local.

Jacob Fugal