package edu.stanford.nlp.sempre;
import com.google.common.base.Function;
import fig.basic.LispTree;
/**
* Aggregate takes a set and computes some number of that set.
* Includes existential quantification.
*
* @author Percy Liang
*/
public class AggregateFormula extends Formula {
public enum Mode {count, sum, mean, min, max, exists};
public final Mode mode;
public final Formula child;
public AggregateFormula(Mode mode, Formula child) {
this.mode = mode;
this.child = child;
}
public LispTree toLispTree() {
LispTree tree = LispTree.proto.newList();
tree.addChild(mode.toString());
tree.addChild(child.toLispTree());
return tree;
}
public static Mode parseMode(String mode) {
if ("count".equals(mode)) return Mode.count;
if ("sum".equals(mode)) return Mode.sum;
if ("mean".equals(mode)) return Mode.mean;
if ("min".equals(mode)) return Mode.min;
if ("max".equals(mode)) return Mode.max;
if ("exists".equals(mode)) return Mode.max;
return null;
}
public Formula map(Function<Formula, Formula> func) {
Formula result = func.apply(this);
return result == null ? new AggregateFormula(mode, child.map(func)) : result;
}
@Override
public boolean equals(Object thatObj) {
if (!(thatObj instanceof AggregateFormula)) return false;
AggregateFormula that = (AggregateFormula) thatObj;
if (!this.mode.equals(that.mode)) return false;
if (!this.child.equals(that.child)) return false;
return true;
}
public int computeHashCode() {
int hash = 0x7ed55d16;
hash = hash * 0xd3a2646c + mode.toString().hashCode();
hash = hash * 0xd3a2646c + child.hashCode();
return hash;
}
}