Class: ActiveModel::Type::Decimal
Relationships & Source Files | |
Extension / Inclusion / Inheritance Descendants | |
Subclasses:
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Super Chains via Extension / Inclusion / Inheritance | |
Class Chain:
self,
Value
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Instance Chain:
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Inherits: |
ActiveModel::Type::Value
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Defined in: | activemodel/lib/active_model/type/decimal.rb |
Overview
Active Model Decimal Type
::ActiveModel::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
-
BIGDECIMAL_PRECISION =
# File 'activemodel/lib/active_model/type/decimal.rb', line 4718
Helpers::Numeric
- Included
Class Method Summary
Value
- Inherited
.new | Initializes a type with three basic configuration settings: precision, limit, and scale. |
Instance Attribute Summary
Value
- Inherited
#limit, #precision, #scale, | |
#binary? | These predicates are not documented, as I need to look further into their use, and see if they can be removed entirely. |
#mutable?, #serialized? |
Instance Method Summary
- #type
- #type_cast_for_schema(value)
- #apply_scale(value) private
- #cast_value(value) private
- #convert_float_to_big_decimal(value) private
- #float_precision private
Helpers::Numeric
- Included
#cast, #changed?, #serialize, #serialize_cast_value, #equal_nan?, #non_numeric_string?, #number_to_non_number? |
Value
- Inherited
#==, #as_json, #assert_valid_value, | |
#cast |
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#changed? | Determines whether a value has changed for dirty checking. |
#changed_in_place? | Determines whether the mutable value has been modified since it was read. |
#deserialize | Converts a value from database input to the appropriate ruby type. |
#eql? | Alias for Value#==. |
#hash, | |
#serializable? | Returns true if this type can convert |
#serialize | Casts a value from the ruby type to a type that the database knows how to understand. |
#type | Returns the unique type name as a |
#cast_value | Convenience method for types which do not need separate type casting behavior for user and database inputs. |
#force_equality?, #map, | |
#type_cast_for_schema |
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#value_constructed_by_mass_assignment? |
SerializeCastValue
- Included
Constructor Details
This class inherits a constructor from ActiveModel::Type::Value
Instance Method Details
#apply_scale(value) (private)
[ GitHub ]# File 'activemodel/lib/active_model/type/decimal.rb', line 98
def apply_scale(value) if scale value.round(scale) else value end end
#cast_value(value) (private)
[ GitHub ]# File 'activemodel/lib/active_model/type/decimal.rb', line 58
def cast_value(value) casted_value = \ case value when ::Float convert_float_to_big_decimal(value) when ::Numeric BigDecimal(value, precision || BIGDECIMAL_PRECISION) when ::String begin value.to_d rescue ArgumentError BigDecimal(0) end else if value.respond_to?(:to_d) value.to_d else cast_value(value.to_s) end end apply_scale(casted_value) end
#convert_float_to_big_decimal(value) (private)
[ GitHub ]# File 'activemodel/lib/active_model/type/decimal.rb', line 82
def convert_float_to_big_decimal(value) if precision BigDecimal(apply_scale(value), float_precision) else value.to_d end end
#float_precision (private)
[ GitHub ]#type
[ GitHub ]# File 'activemodel/lib/active_model/type/decimal.rb', line 49
def type :decimal end
#type_cast_for_schema(value)
[ GitHub ]# File 'activemodel/lib/active_model/type/decimal.rb', line 53
def type_cast_for_schema(value) value.to_s.inspect end