Delia supports inheritance for both scalar and struct types.

Scalar Inheritance

A custom scalar type is a scalar type that you define:

type Temperature int end

It is used in conjuction with validation rules and will be covered there. (See …)

Struct Inheritance

A struct type can inherit from another struct type. The derived type has all the fields of its base type(s).

 type User {
   id int primaryKey
   username String
   password String
 type Customer User {
   lastPurchaseDate date
   shoeSize number

The Customer type will have five fields: id, username, password, lastPurchaseDate, and shoeSize.