allowing objects to specify exception types

gistfile1.rb

class Share
  def call
    list.each do |address|
      begin
        referral = new_referral(address)
        referral.save
      rescue referral.invalid_exception_type
        @unsaved << referral
      end
    end
  end
  
  def new_referral(address)
    Referral.new(address)
  end
end

class Referral
  class Invalid < StandardError; end
  
  def invalid_exception_type
    Referral::Invalid
  end
end

That's interesting. I will ponder this.

See https://gist.github.com/1516514 for an alternative