Thread-safe immutable objects that provide delegation and basic validation to hashes.
class Person < HashDelegator
required :first_name, :last_name
transform_keys(&:to_sym)
def name
"#{first_name} #{last_name}"
end
end
person = Person.new(first_name: "Mary", last_name: "Lamb", age: 32)
person.age # => 32
person.name # => "Mary Lamb"
# it supports all non-mutating methods of Hash
person.merge!(favorite_food: "Thai") # => NoMethodError
person.merge(favorite_food: "Thai") # => #<Person { first_name: "Mary", last_name: "Lamb", age: 32 }>
# respects inheritance
class Employee < Person
required :employee_id
end
Employee.new(age: 32, employee_id: 1234) # => Error, first_name attribute is required
Employee.new(first_name: "John", last_name: "Smith", age: 23, employee_id: 3456) # => #<Employee ...>Because generality...
Add this line to your application's Gemfile:
gem 'hash_delegator'And then execute:
$ bundle install
Or install it yourself as:
$ gem install hash_delegator
The gem is available as open source under the terms of the MIT License.