@Override public Expected<T> ifPresent(final Consumer<? super T> consumer){
  if (this.value != null)   consumer.accept(this.value);
  return this;
}

@ Override public Expected < T > ifPresent ( final Consumer < ? super T > consumer ) { if ( this . value != null ) consumer . accept ( this . value ) ; return this ; }
if a value is present , invoke the consumer with the value .
