ClosedStruct

ClosedStructs work like OpenStruct, with the exception of being immutable and not responding to methods which haven't been listed in the input hash

Add this line to your application's Gemfile:

gem 'closed_struct'

And then execute:

$ bundle

Or install it yourself as:

$ gem install closed_struct

ClosedStruct.new(:a => :b).a # => :b
ClosedStruct.new("a" => :b).a # => :b
ClosedStruct.new(:a => :b).c # => raises NoMethodError

# It won't allow you to have name clashes in the input:

ClosedStruct.new(:a => :b, "a" => :b) # => raises ArgumentError

# You can also attach additional methods to your objects like so:
ClosedStruct.new(:a => :b) do
  def some_method(whatever)
    :something
  end
end

1. Fork it ( https://github.com/obrok/closed_struct/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request