Are inbound arcs relevant or necessary?

I think I have fully grasped the concept of what an inbound arc, as expressed 
in the XLink Rec, may be.

However, I am having significantly more difficulty in grasping what is the 
purpose or relevance of an inbound arc.

Let's suppose a linkbase exists in which there is an arc-type element which 
expresses an inbound arc. What use is it? How does an XLink processor handle 
the situation?

From my simple (simplistic?) perspective the XLink processor isn't allowed to 
traverse an inbound arc by "going up the one-way street the wrong way". So, 
in order to retrieve the supposed starting resource of the inbound arc the 
XLink processor must traverse a corresponding (implicit) outbound arc in 
order to access the "starting resource" of the inbound arc.

Wouldn't it be simpler to express the inbound arc (with its associated 
implicit outbound arc) using a straightforward outbound arc?

Is my take on this correct? When an inbound arc is deemed to exist is there 
typically (always?) a corresponding implicit outbound arc which has to be 
traversed to retrieve the "starting resource" of the inbound arc?

If so, what useful purpose does an inbound arc serve in such a situation?

If there are situations where an inbound arc is needed but a corresponding 
implicit outbound arc isn't actually used can anyone give me a practical 
example of such a scenario?

Andrew Watt

Received on Tuesday, 12 March 2002 00:03:15 UTC