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class ActiveModel::Type::Decimal

Active Model Decimal Type

Attribute type for decimal, high-precision floating point numeric representation. It is registered under the :decimal key.

class BagOfCoffee
  include ActiveModel::Attributes

  attribute :weight, :decimal
end

Numeric instances are converted to BigDecimal instances. Any other objects are cast using their to_d method, except for blank strings, which are cast to nil. If a to_d method is not defined, the object is converted to a string using to_s, which is then cast using to_d.

bag = BagOfCoffee.new

bag.weight = 0.01
bag.weight # => 0.1e-1

bag.weight = "0.01"
bag.weight # => 0.1e-1

bag.weight = ""
bag.weight # => nil

bag.weight = :arbitrary
bag.weight # => nil (the result of `.to_s.to_d`)

Decimal precision defaults to 18, and can be customized when declaring an attribute:

class BagOfCoffee
  include ActiveModel::Attributes

  attribute :weight, :decimal, precision: 24
end

Inherits From

Constants

BIGDECIMAL_PRECISION

18

Public instance methods

type()

Source code GitHub 
# File activemodel/lib/active_model/type/decimal.rb, line 49
def type
  :decimal
end

type_cast_for_schema(value)

Source code GitHub 
# File activemodel/lib/active_model/type/decimal.rb, line 53
def type_cast_for_schema(value)
  value.to_s.inspect
end

Definition files