Class: ActiveModel::Type::Decimal

Inherits:
Value show all
Includes:
Helpers::Immutable, Helpers::Numeric
Defined in:
activemodel/lib/active_model/type/decimal.rb

Overview

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

Constant Summary collapse

BIGDECIMAL_PRECISION = 
18

Instance Attribute Summary

Attributes inherited from Value

#limit, #precision, #scale

Instance Method Summary collapse

Methods included from Helpers::Numeric

#cast, #changed?, #serialize, #serialize_cast_value

Methods included from Helpers::Immutable

#mutable?

Methods inherited from Value

#==, #as_json, #assert_valid_value, #binary?, #cast, #changed?, #changed_in_place?, #deserialize, #force_equality?, #hash, #initialize, #map, #mutable?, #serializable?, #serialize, #serialized?, #value_constructed_by_mass_assignment?

Methods included from SerializeCastValue

included, #initialize, #itself_if_serialize_cast_value_compatible, serialize

Methods included from ActiveSupport::Concern

#append_features, #class_methods, extended, #included, #prepend_features, #prepended

Constructor Details

This class inherits a constructor from ActiveModel::Type::Value

Instance Method Details

#type ⇒ Object 



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# File 'activemodel/lib/active_model/type/decimal.rb', line 50

def type
  :decimal
end

#type_cast_for_schema(value) ⇒ Object 



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# File 'activemodel/lib/active_model/type/decimal.rb', line 54

def type_cast_for_schema(value)
  value.to_s.inspect
end