code: public R applyOrElse(F0<? extends R> fallback) {
              try {
                  return apply();
              } catch (RuntimeException e) {
                  return fallback.apply();
              }
          }
docs: Applies this partial function to the given argument when it is contained in the function domain.
  Applies fallback function where this partial function is not defined, i.e. any
  {@link java.lang.RuntimeException} is captured
  
  @param fallback
  if {@link RuntimeException} captured then apply this fallback function
  @return the result of this function or the fallback function application