IS THE CANON OF SCRIPTURE FULL?

The following words of St. John are supposed by some to imply that no more revelation is to be given:

"For I testify unto every man that heareth the words of the prophecy of this book, If any man shall add unto these things, God shall add unto him the plagues that are written in this book. (Revelation 22: 18).

The apostle here only warns man against adding to the words of the prophecy of his book. He says nothing about the Bible as a whole; nor does he say that God will not add any more revelations to His word.