a "modest proposal" for PRD

Start with exactly the BLD syntax.  Add just 1 or 2 "hard" things (e.g. 
retraction and rule priority) that are common in PR and make a model 
theory very difficult.  Do not respecify the syntax, just add the new 
elements.  Develop an Operational Semantics for it, as defined by 
Plotkin in http://homepages.inf.ed.ac.uk/gdp/publications/sos_jlap.pdf.  
Do not spend time on informal semantics that can only diverge from the 
formal semantics.  Only after PRD has caught up with BLD in terms of 
semantic rigor should it incorporate negation, aggregation, other 
actions, etc.

The task of developing a formal Operational Semantics for PRD is not 
trivial and would be best attempted by someone who has done something 
similar before.

-- 


Oracle <http://www.oracle.com>
Gary Hallmark | Architect | +1.503.525.8043
Oracle Server Technologies
1211 SW 5th Avenue, Suite 800
Portland, OR 97204

Received on Wednesday, 20 February 2008 09:40:20 UTC