package org.basex.query.expr;
import java.io.IOException;
import org.basex.io.serial.Serializer;
import org.basex.query.QueryContext;
import org.basex.query.util.Var;
import org.basex.util.InputInfo;
/**
* Simple expression without arguments.
*
* @author BaseX Team 2005-12, BSD License
* @author Christian Gruen
*/
public abstract class Simple extends ParseExpr {
/**
* Constructor.
* @param ii input info
*/
protected Simple(final InputInfo ii) {
super(ii);
}
@Override
public Expr comp(final QueryContext ctx) {
return this;
}
@Override
public boolean uses(final Use u) {
return false;
}
@Override
public int count(final Var v) {
return 0;
}
@Override
public boolean removable(final Var v) {
return true;
}
@Override
public Expr remove(final Var v) {
return this;
}
@Override
public void plan(final Serializer ser) throws IOException {
ser.emptyElement(this);
}
}