caller_abstraction.rb

class Result
  def self.successful
    Result.new(true)
  end
  def self.failed(message)
    Result.new(false,message)
  end

  attr_reader :message
  def initialize(succeeded,message=nil)
    @succeeded = succeeded
    @message
  end

  def succeeded?; @succeeded; end
end

class Caller
  def call(step,current_result)
    if current_result.succeeded?
      step.process
    else
      current_result
    end
  end
end

class Step1
  def process
    if worky
      Result.successful
    else
      Result.failed("No worky!")
    end
  end
end

class Step2
  def process
    if awesome
      Result.successful
    else
      Result.failed("not Awesome :(")
    end
  end
end

class Step3
  def process
    if has_sad?
      Result.failed("HAD SAD")
    else
      Result.successful
    end
  end
end

caller = Caller.new

result = [Step1,Step2,Step3].reduce(Result.successful) { |acc,step| acc = caller.call(step,acc) }

I think it's unnecessary to assign to acc in the reduce block.