Re: Discriminated records are not the most efficient, but ...

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Mon, 23 Aug 2010 10:26:28 +0200, Yannick Duchêne (Hibou57) wrote:

> Le Mon, 23 Aug 2010 10:06:46 +0200, Dmitry A. Kazakov  
> <mailbox@dmitry-kazakov.de> a écrit:
>> Nominal type equivalence is when two types considered same when their  
>> names are same. It cannot imply structural typing.
> Should have said “Full Name” instead of Name.

No matter, it is the names which are matched, not the objects they denote.
Names themselves can be matched in different ways, e.g. Foo = foO,
Standard.Integer = Integer etc.

> In Ada, same full name (after any renaming resolution done) implies the  
> same structure, or implies it holds at least the same structure (if you  
> consider the views of a type of a class), which is enough to hold logical  
> properties inferred from the structure.

This require definition of "structure". The language at least tries to
avoid references to the structure, because it break fundamental concepts of
the language design (abstractness, information hiding, separation of
interface and implementation etc). If you replace "structure" to "behavior"
then, yes, same thing has same behavior.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de