TreeStruct

Welcome to your new gem! In this directory, you'll find the files you need to be able to package up your Ruby library into a gem. Put your Ruby code in the file lib/tree_struct. To experiment with that code, run bin/console for an interactive prompt.

TODO: Delete this and the text above, and describe your gem

Installation

Add this line to your application's Gemfile:

gem 'tree_struct'

And then execute:

$ bundle

Or install it yourself as:

$ gem install tree_struct

Usage

It is used as the parent class for FormObj::Form

Table of Contents

1. Definition
   1. Nested TreeStruct
   2. Array of TreeStruct
2. Serialize to Hash
   1. Nested TreeStruct
   2. Array of TreeStruct
3. Reference Guide

1. Definition

Inherit your class from TreeStruct and define its attributes.

class SimpleTreeStruct < TreeStruct
  attribute :name
  attribute :year
end

Access attributes via dot notation.

simple_tree_struct = SimpleTreeStruct.new
simple_tree_struct.name = 'Ferrari'         # => "Ferrari"
simple_tree_struct.year = 1950              # => 1950

1.1. Nested TreeStruct Objects

Use blocks to define nested TreeStruct.

class NestedTreeStruct < TreeStruct
  attribute :name
  attribute :year
  attribute :car do
    attribute :model
    attribute :driver
    attribute :engine do
      attribute :power
      attribute :volume
    end
  end
end

Or explicitly define nested TreeStruct classes.

class EngineTreeStruct < TreeStruct
  attribute :power
  attribute :volume
end
class CarTreeStruct < TreeStruct
  attribute :model
  attribute :driver
  attribute :engine, class: EngineTreeStruct
end
class NestedTreeStruct < TreeStruct
  attribute :name
  attribute :year
  attribute :car, class: CarTreeStruct
end

Access attributes via dot notation.

nested_tree_struct = NestedTreeStruct.new
nested_tree_struct.name = 'Ferrari'         # => "Ferrari"
nested_tree_struct.year = 1950              # => 1950
nested_tree_struct.car.model = '340 F1'     # => "340 F1"
nested_tree_struct.car.driver = 'Ascari'    # => "Ascari"
nested_tree_struct.car.engine.power = 335   # => 335
nested_tree_struct.car.engine.volume = 4.1  # => 4.1

1.2. Array of TreeStruct Objects

Specify attribute parameter array: true in order to define an array of TreeStruct objects

class ArrayTreeStruct < TreeStruct
  attribute :name
  attribute :year
  attribute :cars, array: true do
    attribute :model
    attribute :driver
    attribute :engine do
      attribute :power
      attribute :volume
    end
  end
end

or

class EngineTreeStruct < TreeStruct
  attribute :power
  attribute :volume
end
class CarTreeStruct < TreeStruct
  attribute :model
  attribute :driver
  attribute :engine, class: EngineTreeStruct
end
class ArrayTreeStruct < TreeStruct
  attribute :name
  attribute :year
  attribute :cars, array: true, class: CarTreeStruct
end

Add new elements in the array by using method :create which adds a new it.

array_tree_struct = ArrayTreeStruct.new
array_tree_struct.name = 'Ferrari'              # => "Ferrari"
array_tree_struct.year = 1950                   # => 1950
array_tree_struct.size                          # => 0
array_tree_struct.cars.create
array_tree_struct.size                          # => 1
array_tree_struct.cars[0].model = '340 F1'      # => "340 F1"
array_tree_struct.cars[0].driver = 'Ascari'     # => "Ascari"
array_tree_struct.cars[0].engine.power = 335    # => 335
array_tree_struct.cars[0].engine.volume = 4.1   # => 4.1

2. Serialize to Hash

Call to_hash method in order to get hash representation of the TreeStruct object

simple_tree_struct.to_hash      # => {
                                # =>    :name => "Ferrari",
                                # =>    :year => 1950  
                                # => }

2.1. Nested TreeStruct Objects

nested_tree_struct.to_hash      # => {
                                # =>    :name => "Ferrari",
                                # =>    :year => 1950,
                                # =>    :car  => {
                                # =>      :model => "340 F1",
                                # =>      :driver => "Ascari",
                                # =>      :engine => {
                                # =>        :power => 335,
                                # =>        :volume => 4.1
                                # =>      }   
                                # =>    }
                                # => }

3.2. Array of TreeStruct Objects

array_tree_struct.to_hash       # => {
                                # =>    :name => "Ferrari",
                                # =>    :year => 1950,
                                # =>    :cars => [{
                                # =>      :model => "340 F1",
                                # =>      :driver => "Ascari",
                                # =>      :engine => {
                                # =>        :power => 335,
                                # =>        :volume => 4.1
                                # =>      }
                                # =>    }] 
                                # => }

3. Reference Guide: attribute parameters

Parameter	Condition	Default value	Description
array	block* or :class**	false	This attribute is an array of TreeStruct objects. The structure of array element is described either in the block or in the separate class referenced by :class parameter
class	-	-	This attribute is either nested TreeStruct object or an array of TreeStruct objects. The value of this parameter is a class or a name of a class of this TreeStruct object.

* block - means that there is block definition for the attribute

** :class - means that this attribute has :class parameter specified

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/akoltun/tree_struct.

License

The gem is available as open source under the terms of the MIT License.