Re: [seul-edu] some remarks on EDUML

[Bruno Vernier <vernier@vc.bc.ca>]

On Wed, Feb 09, 2000 at 09:54:21PM +0800, Hilaire Fernandes wrote:

> Todays I've printed the EDUML DTD proposal - the french traduction by
> Odile more exactly - and study some part of it. I want to make some
> remarks, that may not be accurate at all as i'm new to eduml.

Great! Peer review!

> I've saw that the "id" attribute is use both to give an unique
> identifier when defining a new entity (or element I'm not sure which
> term to use there) or when referencing to an entity.  It could help to
> the lecture if instead a "ref" attribute was used when referencing to
> an entity (or element).

I agree.  I'll change it to "ref" if no one else objects.  The attribute
"id" leads to some other problems in zope (conflict of attributes caused by
inheritance which I will explain below) because zope uses "id" as an
attribute for all objects in its world.

> What is the id of a people element? I suspect it is the login
> attribute but it ma be better to add an id attribute as well. Each one
> with its own function.

yes, the id of people is the login attribute which we could change to
"login"

> Is it necessary to duplicate element and attribute ? This will produce
> less consistent eduml document - uniform from one document to another.
> It will probably not hurt to decide what shoud be an element and an
> attribute.
> <EMAIL email="zozo"/>, <EMAIL>zozo</EMAIL> is better i think.  <URL
> url="goto"/>, <URL>goto</URL> is better i think.
> <MEMBER id="person-id"></MEMBER> should/could be <MEMBER
> ref="person-id"/>

see my previous email (which I think I sent to this list); basically, I
found advantages to both ways, and so left both alternates in.  I realise it
would be ideal to have just one way;  but it is quite arbitrary in my
opinion which way to go; for example, the login name can easily be an
attribute or an element ... 

> Why in the SCHOOL element attributes are named school_id, school_url,
> school_icon, school_org instead of simply id, url, icon, org. The
> school_ prefix is not useful as this is attribute of a SCHOOL element.

There is a practical reason for this!  It is because of "inheritance"
in some systems;  when you read an XML data file, if you do not use some
attributes at a particular element level, then (zope for example) will use
inheritance and go to the Parents of the element to look for that attribute.
Therefore each level must have unique attribute names unless it really is
the same attribute in different levels.  Otherwise; major confusion!

Again, thanks for your peer review :-)

Bruno