docs: public static Procedure0 andThen(final Procedure0 before, final Procedure0 after) {
  		if (after == null)
  			throw new NullPointerException("after");
  		if (before == null)
  			throw new NullPointerException("before");
  		return new Procedures.Procedure0() {
  			@Override
  			public void apply() {
  				before.apply();
  				after.apply();
  			}
  		};
  	}