:default - The default value for the attributes. If
the value is a proc or lambda, it will be called whenever an instance
is constructed. Otherwise, the value will be duplicated with #dup.
Default values are re-assigned when the attributes are
reset.
# File activesupport/lib/active_support/current_attributes.rb, line 114
def attribute(*names, default: NOT_SET)
invalid_attribute_names = names.map(&:to_sym) & INVALID_ATTRIBUTE_NAMES
if invalid_attribute_names.any?
raise ArgumentError, "Restricted attribute names: #{invalid_attribute_names.join(", ")}"
end
Delegation.generate(singleton_class, names, to: :instance, nilable: false, signature: "")
Delegation.generate(singleton_class, names.map { |n| "#{n}=" }, to: :instance, nilable: false, signature: "value")
ActiveSupport::CodeGenerator.batch(generated_attribute_methods, __FILE__, __LINE__) do |owner|
names.each do |name|
owner.define_cached_method(name, namespace: :current_attributes) do |batch|
batch <<
"def #{name}" <<
"attributes[:#{name}]" <<
"end"
end
owner.define_cached_method("#{name}=", namespace: :current_attributes) do |batch|
batch <<
"def #{name}=(value)" <<
"attributes[:#{name}] = value" <<
"end"
end
end
end
self.defaults = defaults.merge(names.index_with { default })
end
