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= Attribute Cartographer

* http://github.com/krishicks/attribute-cartographer

== DESCRIPTION

Attribute Cartographer allows you to map an attributes hash into similarly or differently named methods, using an optional lambda to map the values as well.

== INSTALL

Add attribute-cartographer to your Gemfile

  gem 'attribute-cartographer'

Then run:

  $ bundle

== USAGE
  class Mapper
    include AttributeCartographer

    # one-way mapping
    map "UnchangedKey"                                                              # map a single key, value untouched
    map %w{ UnchangedKey1 UnchangedKey2 }                                           # same as above, but for multiple in a single statement

    map "SameKeyNewValue", ->(v) { v.downcase }                                     # maps the key, using the lambda for the value
    map %w{ SameKeyNewValue1 SameKeyNewValue2 }, ->(v) { v.upcase }                 # same as above, but for multiple in a single statement

    map "OldKey", "new_key", ->(v) { v.downcase }                                   # maps the left key to the right key, using the lambda for the value
    map "DowncasedKeyAndValue", ->(k,v) { [k.downcase, v.downcase] }                # maps the key and value using the lambda for both
    map %w{ NewKeyAndValue1 NewKeyAndValue2 }, ->(k,v) { [k.downcase, v.downcase] } # same as the example above, but for multiple in a single statement

    # two-way mapping
    map "AnotherOldKey", "another_new_key"                                          # map the left key to the right key and vice-versa, value untouched
    map "ThisKey", "to_this_key", ->(v) { v.downcase }, ->(v) { v.upcase }          # map the left key to the right key with the first lambda,
                                                                                    # and the right key to the left key with the second lambda

  end

  Mapper.new("UnchangedKey" => "UnchangedValue", "OldKey" => "OldValue")            # etc. 

  For each mapping defined, an entry in mapped_attributes will be made using the
  logic defined in the mapping. You also get another method, original_attributes,
  that retains the entire hash that was passed to #initialize, whether the keys
  were mapped or not.

== REQUIREMENTS

* Ruby 1.9.x

== LICENSE

MIT