uk.ac.bbk.dcs.automed.qproc
Interface BuiltInFunction

All Known Implementing Classes:

And, Append, Average, BagIntersect, CallToWrapper, Comprehension, Count, Disjunction, Divide, Equals, First, Flatmap, Foldl, Foldr, generateId, Greater, GreaterEqual, Group, Id, If, Less, LessEqual, Let, LoadListFromFile, Map, Max, Member, Min, Minus, Monus, Multiply, Not, NotEqual, Or, Plus, Second, Single, Sort, SortDistinct, SubBag, Sum

public interface BuiltInFunction

Interface class for all functions.

Method Summary

int	getArity() Returns the arity of the function.
Cell	perform(Cell[] args, Evaluator e) Returns a Cell object that is the root of a graph that represents the result of applying the built-in function to the arguments args.

Method Detail

getArity

public int getArity()

Returns the arity of the function.

perform

public Cell perform(Cell[] args,
                    Evaluator e)

Returns a Cell object that is the root of a graph that represents the result of applying the built-in function to the arguments args. Uses the Evaluator e to evaluate any sub-queries that need to be evaluated.