Nested Structs
The DSL allows to define nested structs by passing a block to attribute:
class User < Dry::Struct
attribute :name, Types::String
attribute :address do
attribute :city, Types::String
attribute :street, Types::String
end
end
User.new(name: 'Jane', address: { city: 'London', street: 'Oxford' })
# => #<User name="Jane" address=#<User::Address city="London" street="Oxford">>
# constants for nested structs are automatically defined
User::Address
# => User::Address
By default, new struct classes uses Dry::Struct as a base class (Dry::Struct::Value for values). You can explicitly pass a different class:
class User < Dry::Struct
attribute :address, MyStruct do
# ...
end
end
It is even possible to define an array of struct:
class User < Dry::Struct
attribute :addresses, Types::Array do
attribute :city, Types::String
attribute :street, Types::String
end
end
# constants are still there!
User::Address
# => User::Address