[xacml] re: functions

Polar,

 

I agree with the approach where where ERROR in 
evaluating 'or', 'and'

is used as placeholder until 
all components are evaluated.

 

Then, if 
ERROR can be substituted with either (true, false) without changing result, 
result is returned.

If this substitution can not be made, error is 
returned.

'and': false, ERROR, true -> false

'and': true, ERROR, true -> ERROR

'or': false, ERROR, true -> false

'or' true, ERROR, true -> true

 

I'm still not sure what is the purpose of error 
functions.

If an error is raised, there is a prescription of 
what must be done

during condition evaluation and rule 
evaluation.

 

Even if we had error functions there is no syntax 
to accomodate them.

Also, what to do if error-handling function is 
raising an error, such as invalid default value etc?

Simon