code: public static LongBinding subtractExact(final ObservableLongValue x, final ObservableLongValue y) {
          return createLongBinding(() -> Math.subtractExact(x.get(), y.get()), x, y);
      }
docs: Binding for {@link java.lang.Math#subtractExact(long, long)}
  
  @param x the first value
  @param y the second value to subtract from the first
  @return the result
  @throws ArithmeticException if the result overflows a long