module ActiveModel::Attributes::ClassMethods

def attribute(name, ...)

person.active # => true
person.name # => "Volmer"

person.name = "Volmer"
person = Person.new

end
attribute :active, :boolean, default: true
attribute :name, :string

include ActiveModel::Attributes
class Person

supported by the given cast type.
type and default value may be specified, as well as any options
Defines a model attribute. In addition to the attribute name, a cast

:call-seq: attribute(name, cast_type = nil, default: nil, **options)
# 
def attribute(name, ...)
  super
  define_attribute_method(name)
end

def attribute_names

Person.attribute_names # => ["name", "age"]

end
attribute :age, :integer
attribute :name, :string

include ActiveModel::Attributes
class Person

Returns an array of attribute names as strings. 
def attribute_names
  attribute_types.keys
end

def define_method_attribute=(canonical_name, owner:, as: canonical_name) 

def define_method_attribute=(canonical_name, owner:, as: canonical_name)
  ActiveModel::AttributeMethods::AttrNames.define_attribute_accessor_method(
    owner, canonical_name, writer: true,
  ) do |temp_method_name, attr_name_expr|
    owner.define_cached_method(temp_method_name, as: "#{as}=", namespace: :active_model) do |batch|
      batch <<
        "def #{temp_method_name}(value)" <<
        "  _write_attribute(#{attr_name_expr}, value)" <<
        "end"
    end
  end
end