public function parse($input)
    {
        if (strlen($input) == 0) {
            return null;
        }
        return $this->parser->parse(new TokenStream($this->tokenizer->getTokens($input)));
    }
public function parse($input)
    {
        if (strlen($input) == 0) {
            return null;
        }
        return $this->parser->parse(new TokenStream($this->tokenizer->getTokens($input)));
    }
public function parse ( $ input ) { if ( strlen ( $ input ) == 0 ) { return null ; } return $ this -> parser -> parse ( new TokenStream ( $ this -> tokenizer -> getTokens ( $ input ) ) ) ; }
Parses the raw string input and returns the resulting root node.

@param string $input
@return Node
Parses the raw string input and returns the resulting root node .