Don't use variables in step_defs

bad_step_def.rb

require 'rubygems'
require 'mechanize'
require 'json'

module ApiExtensions

    @agent = Mechanize.new
    @api_header = {'Accept' => 'application/json', 'Content-Type' => 'application/json'}
    @api_uris = {
        'the list of campuses' => 'http://example.com/servicehosts/campus.svc',
        'the list of settings' => 'http://example.com/servicehosts/setting.svc',
        'login' => 'http://example.com/servicehosts/Student.svc/login',
    }    
    # some methods  
end

World(ApiExtensions)

better_step_def.rb

require 'rubygems'
require 'mechanize'
require 'json'

module ApiExtensions
  def mechanize_agent
    Mechanize.new
  end

  def api_json_header
    {'Accept' => 'application/json', 'Content-Type' => 'application/json'}
  end
  
  def api_uris
    {
        'the list of campuses' => 'http://example.com/servicehosts/campus.svc',
        'the list of settings' => 'http://example.com/servicehosts/setting.svc',
        'login' => 'http://example.com/servicehosts/Student.svc/login',
    }    
  end  
  # some methods  
  
end

World(ApiExtensions)