code: public Instant minusNanos(long nanosToSubtract) {
          if (nanosToSubtract == Long.MIN_VALUE) {
              return plusNanos(Long.MAX_VALUE).plusNanos(1);
          }
          return plusNanos(-nanosToSubtract);
      }
docs: Returns a copy of this instant with the specified duration in nanoseconds subtracted.
  <p>
  This instance is immutable and unaffected by this method call.
  
  @param nanosToSubtract  the nanoseconds to subtract, positive or negative
  @return an {@code Instant} based on this instant with the specified nanoseconds subtracted, not null
  @throws DateTimeException if the result exceeds the maximum or minimum instant
  @throws ArithmeticException if numeric overflow occurs