Configuration

• 25

  JUN
  2008

  The One Method Config

  I've used this technique a couple of times now for dirt-simple configurations. The idea is to provide a trivial way to read and write configuration values with just a single method. Let me show you what I mean:

  module Configurable
    module_function
  
    def config(new_config = nil)
      if new_config.nil?
        @config ||= { }
      else
        config.merge!(new_config)
      end
    end
  end
  
  include Configurable
  
  config                    # => {}
  
  config :a => 1, :b => 2
  config                    # => {:a=>1, :b=>2}
  config[:a]                # => 1
  
  config :a => -1, :c => 3
  config                    # => {:a=>-1, :b=>2, :c=>3}
  
  config.clear
  config                    # => {}
  

  There's no deep magic here, obviously. The method has two function: read and write for the configuration. Read is handled with what I like refer to as Ruby's "caching operator" (||=). The first time that line is triggered, it will cache an empty Hash in the variable. Thereafter, the same call is just a cache hit to get the same Hash back.

  Read more…

  In: Ruby Voodoo | Tags: Configuration & APIs | 2 Comments