Module | DataMapper::Validations::ValidatesPresence |
In: |
lib/dm-validations/validators/required_field_validator.rb
|
Validates that the specified attribute is present.
For most property types "being present" is the same as being "not blank" as determined by the attribute‘s blank? method. However, in the case of Boolean, "being present" means not nil; i.e. true or false.
@note
dm-core's support lib adds the blank? method to many classes,
@see lib/dm-core/support/blank.rb (dm-core) for more information.
@example Usage
require 'dm-validations' class Page include DataMapper::Resource property :required_attribute, String property :another_required, String property :yet_again, String validates_presence_of :required_attribute validates_presence_of :another_required, :yet_again # a call to valid? will return false unless # all three attributes are !blank? end