code: public static FuncN<Void> fromAction(final Action0 f) {
          return new FuncN<Void>() {
  
              @Override
              public Void call(Object... args) {
                  if (args.length != 0) {
                      throw new RuntimeException("Action0 expecting 0 arguments.");
                  }
                  f.call();
                  return null;
              }
  
          };
      }
docs: Converts an {@link Action0} to a {@link FuncN} to allow heterogeneous handling of functions with different arities.
  
  @param f the {@code Action0} to convert
  @return a {@link FuncN} representation of {@code f}