Active Model Integer Type

Attribute type for integer representation. This type is registered under the :integer key.

class Person
  include ActiveModel::Attributes

  attribute :age, :integer
end

Values are cast using their to_i method, except for blank strings, which are cast to nil. If a to_i method is not defined or raises an error, the value will be cast to nil.

person = Person.new

person.age = "18"
person.age # => 18

person.age = ""
person.age # => nil

person.age = :not_an_integer
person.age # => nil (because Symbol does not define #to_i)

Serialization also works under the same principle. Non-numeric strings are serialized as nil, for example.

Serialization also validates that the integer can be stored using a limited number of bytes. If it cannot, an ActiveModel::RangeError will be raised. The default limit is 4 bytes, and can be customized when declaring an attribute:

class Person
  include ActiveModel::Attributes

  attribute :age, :integer, limit: 6
end