%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% File: entity.db
% This file is used by the business model simulator.

% :- multifile entity/2.

/*************************************************************
entity(Instance, Entity, Attribute). 

Attribute = list, a list of Attribute/value items, that describes
            the attributes of entity, e.g.
            entity(john, Person, [sex/male, age/25,...]). 

--------------------------------------
examples used in a WFS working memory: 

entity(john, customer, [sex/male, dob/01Jan1977, 
                        some-email@address.com, event/[t1] ]). 

special_req(Board, Attribute, Value)

Board = a class. 
Attribute = a string. 
Value = an atom. 

------------------------------------
examples predicates in an Entity Database:

instance_of(john, customer). 
instance_att(john, event, e1). 

instance_of(e1, event). 

instance_att(e1, solution, Solution/5). 

------------------------------------
solution/5: 
solution(+Customer, +Requirements, 
         +Old_sol,  -New_sol, -Difference). 

------------------------------------
Role:  name/role: 

edinburgh/pc_specification
edinburgh/marketing
aberdeen/technology 

*************************************************************/