IncrementalDecoder.decode().
Decodes \var{object} (taking the current state of the decoder into account)
and returns the resulting decoded object. If this is the last call to
\method{decode} \var{final} must be true (the default is false).
+ If \var{final} is true the decoder must decode the input completely and must
+ flush all buffers. If this isn't possible (e.g. because of incomplete byte
+ sequences at the end of the input) it must initiate error handling just like
+ in the stateless case (which might raise an exception).
\end{methoddesc}
\begin{methoddesc}{reset}{}