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Methods
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Instance Public methods

attribute(name, cast_type = nil, default: nil, **options)

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

class Person
  include ActiveModel::Attributes

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

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

person.name   # => "Volmer"
person.active # => true
# File activemodel/lib/active_model/attributes.rb, line 59
def attribute(name, ...)
  super
  define_attribute_method(name)
end

attribute_names()

Returns an array of attribute names as strings.

class Person
  include ActiveModel::Attributes

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

Person.attribute_names # => ["name", "age"]
# File activemodel/lib/active_model/attributes.rb, line 74
def attribute_names
  attribute_types.keys
end

type_for_attribute(attribute_name, &block)

Returns the type of the specified attribute after applying any modifiers. This method is the only valid source of information for anything related to the types of a model’s attributes. The return value of this method will implement the interface described by ActiveModel::Type::Value (though the object itself may not subclass it).

# File activemodel/lib/active_model/attributes.rb, line 79