Re: [Caml-list] obj magic performance and other questions

[Dario Teixeira <darioteixeira@yahoo.com>]

Hi,

> I need to simulate, in Ocaml, the extensible records of
> Oberon. I am doing the
> following:
> 
> Oberon type declaration:
> 
> TYPE
> 
> rec1 = RECORD a : INTEGER END;
> rec2 = RECORD (rec1) b : CHAR END;
> rec3 = RECORD (rec1) c : REAL END;

Have you considered leveraging the structural subtyping features of the object system, or do you reckon the (small) performance penalty is too
great?

type rec1 = < a: int >
type rec2 = < a: int; b: char >
type rec3 = < a: int; c: float >

let make_rec1 a =
object
  method a = a
end

let make_rec2 a b =
object
  method a = a
  method b = b
end

...and so forth.

Best regards,
Dario Teixeira