class ActiveRecord::Type::Value
Attributes
Public Class Methods
# File activemodel/lib/active_model/type/value.rb, line 6 def initialize(precision: nil, limit: nil, scale: nil) @precision = precision @scale = scale @limit = limit end
Public Instance Methods
# File activemodel/lib/active_model/type/value.rb, line 91 def ==(other) self.class == other.class && precision == other.precision && scale == other.scale && limit == other.limit end
# File activemodel/lib/active_model/type/value.rb, line 103 def assert_valid_value(*) end
# File activemodel/lib/active_model/type/value.rb, line 35 def cast(value) cast_value(value) unless value.nil? end
Type casts a value from user input (e.g. from a setter). This value may be a string from the form builder, or a ruby object passed to a setter. There is currently no way to differentiate between which source it came from.
The return value of this method will be returned from ActiveRecord::AttributeMethods::Read#read_attribute. See also: #cast_value.
value
The raw input, as provided to the attribute setter.
# File activemodel/lib/active_model/type/value.rb, line 62 def changed?(old_value, new_value, _new_value_before_type_cast) old_value != new_value end
Determines whether a value has changed for dirty checking. old_value
and new_value
will always be type-cast. Types should not need to override this method.
# File activemodel/lib/active_model/type/value.rb, line 83 def changed_in_place?(raw_old_value, new_value) false end
Determines whether the mutable value has been modified since it was read. Returns false
by default. If your type returns an object which could be mutated, you should override this method. You will need to either:
-
pass
new_value
to #serialize and compare it toraw_old_value
or
-
pass
raw_old_value
to #deserialize and compare it tonew_value
raw_old_value
The original value, before being passed to deserialize
.
new_value
The current value, after type casting.
# File activemodel/lib/active_model/type/value.rb, line 21 def deserialize(value) cast(value) end
Converts a value from database input to the appropriate ruby type. The return value of this method will be returned from ActiveRecord::AttributeMethods::Read#read_attribute. The default implementation just calls #cast.
value
The raw input, as provided from the database.
# File activemodel/lib/active_model/type/value.rb, line 99 def hash [self.class, precision, scale, limit].hash end
# File activemodel/lib/active_model/type/value.rb, line 43 def serialize(value) value end
Casts a value from the ruby type to a type that the database knows how to understand. The returned value from this method should be a String
, Numeric
, Date
, Time
, Symbol
, true
, false
, or nil
.
Private Instance Methods
# File activemodel/lib/active_model/type/value.rb, line 111 def cast_value(value) # :doc: value end
Convenience method for types which do not need separate type casting behavior for user and database inputs. Called by #cast for values except nil
.
© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.