Gradual Typing Using Union Typing With Records

Dynamic typed languages are characterized by their expressiveness and flexibility to develop prototypes, while static typed languages allow early detection of errors and the optimization of source code. Gradual typing languages allow programmers to make use of both approaches, static and dynamic typing, and thus, obtaining the advantages that both represent. The objective here is to revisit the static part of the approach to a gradual interpretation of union types based on the design of Gradual Union Types through an extension with the record data-structure. This contributes to understand the abstraction and reasoning behind Gradual Typing in order to have useful future extensions for other data-structures.