Re: [ooc-compiler] WITH statement and parametric types

[Michael v. A. <mic...@gm...>]

On 6/26/05, vedmed <ve...@in...> wrote:
> I declare parametric type, and want to redefine procedure "Equals":
> [...]
>=20
> But in this example "Equal" always return FALSE, because of WITH
> statement can not recognize parameter "y" as value of type "Alp" or
> "Gam". Expressions "WITH y: Alp DO" and "WITH y: Alp(Object.Object) DO"
> also not works. So I can't see a way how to get access to field "val" of
> parameter "y". I don't know it is bug of compiler or some logic problem.
> I suppose that full check of type and all of him parameters is difficult
> task for compiler and can slow down compiled programs, but I assume,
> that in most cases will be enough only checks of base type.

The current implementation cannot cope with types on the right hand
side of a type test that include a type variable.  It is fundamentally=20
flawed.  Unfortunately I botched a test case half a year ago, or I would
have known this earlier.

I don't know a workaround, and there is no easy fix.  I will have to
think about this some more.

-- mva