package yokohama.unit.position;

import lombok.Value;

@Value
public class Position {
    private int line;
    private int column;

    public static Position of(int line) {
        return new Position(line, -1);
    }

    public static Position of(int line, int column) {
        return new Position(line, column);
    }

    private static Position dummyPos = new Position(-1, -1);
    public static Position dummyPos() {
        return dummyPos;
    }
}

@@ -131,24 +131,105 @@
  column;%0D%0A%0D%0A
+    public boolean isDummy() %7B%0D%0A        return line %3C 0 && column %3C 0;%0D%0A    %7D%0D%0A%0D%0A
     public s

Add Position.isDummy method