12. The method of claim 9 , further comprising the character processing unit providing an output that can then be used to further control the received character stream processing operation.
9. A method of pattern-matching characters in a stream of received characters, the method comprising: storing at least one of a plurality of characters in a character processing unit comprising means for storing characters; selectively providing at least one of a plurality of characters from a received input character stream of a document to the character processing unit; controlling the character processing unit to compare a received input character with at least one of the characters stored by the character processing unit; assessing characters in the received input character stream and then selectively controlling and using the character processing unit according to the assessing; receiving feedback from the character processing unit as to whether the characters from the received input character stream match the characters stored by the character processing unit; and parsing the document based on the feedback received.