Reflection

[Anders Petersson]

>On Tue, Jan 01, 1980 at 01:34:58AM -0800, Tril wrote:
>> On Fri, 1 Jan 1999, Anders Petersson wrote:

[snip: linking in all information]
>Was that more concrete?

Yes, thanks. The question is whether this is your personal view or the
"official" version, and if your wish to actually do this in Tunes - you
said "One example of how an existing system ...".

>>> What speaks against is that mOS shows the user the true system
topology. It
>>> is not as I understand Tunes does - to present the user with a view
that is
>>> independent of the underlaying structures.
>> 
>> There is a view that is independent of underlying structures, but the user
>> can cross it.  Normally there will just be a warning message that says,
>> "if you go here and change stuff, it won't be platform-independent
>> anymore."  You can still do stuff there, and it's all still objects.  I
>> expect lots of hackers to do this.  It will be necessary to spend time
>> here in order to find optimizations to make the system fast.
>
>My understanding is that the intent of Tunes is to allow people to
>specify lower-level information as much as they want, but to never
>require that lower-level optimization information to run the
>functional code. Cases which deal with low-level issues like hardware
>access do not fall into this category because the low-level issues are
>part of the required functional description.

Lovely, another - maybe even blurrier - version. This is just getting
better. (irony)

>>> As reflection changes the way the system is structured, without any
>>> help from the user, reflection could confuse for the user by
>>> changing the way *the user* sees the system.
>
>Certainly. I'd like to rephrase what you said. The more indirection
>which is possible in a system, the more confusing it is going to
>be. Directness is much easier to understand. However, directness is
>also much harder to maintain. I personally think the challenge of
>presenting a system like Tunes is to find a way to represent a
>reflective system in a direct way.

That's not quite what I meant. What if a user learns how his system look,
but abra kadabra, reflection does its job. Where is now that report? "In a
better place" the reflection algorithm would say, but we all know how
stupid algorithms are. Remember that newbies have a hard time just
understanding an ordinary directory structure.

binEng