/*!
* @class WordGraph
*
* @extends Automaton
*
* @headerfile <seqan/graph_type.h>
*
* @brief A special automaton that stores words instead of single characters
* along its edges.
*
* @signature template <[typename TAlphabet[, typename Spec]]> class
* Graph<Automaton<TAlphabet, String<TAlphabet>, WordGraph<TSpec> >;
*
* @tparam TAlphabet The alphabet type.
* @tparam TSpec The specializing types.
*
* @fn WordGraph#getSuccessor
*
* @brief Gets the successor for a given vertex and an edge label.
*
* @signature TVertexDescriptor getSuccessor(a, v, str);
*
* @param[in] a The WordGraph to query for its successor.
* @param[in] v The descriptor fo the vertex to get the successor for.
* @param[in] str The label.
*
* @return TVertexDescriptor A vertex descriptor or nil if successor is not
* defined.
*
* @see WordGraph#parseString
* @see Graph#getNil
*
* @fn WordGraph#parseString
*
* @brief Parses a string one character at a time and moves accordingly in the
* WordGraph.
*
* @signature TVertexDescriptor parseString(a, v, beginIt, endIt);
* @signature TVertexDescriptor parseString(a, v, str);
*
* @param[in] a An WordGraph.
* @param[in] v The descriptor of the vertex to start at.
* @param[in] str The @link SequenceConcept @endlink to parse.
* @param[in,out] beginIt Begin iterator to sequence to parse. Set to the first
* character that could not be parsed or to the value of
* endIt if all of the string was parsed.
* @param[in] endIt End iterator to sequence to parse.
*
* @return TVertexDescriptor The vertex descriptor of the state that was reached
* after parsing.
*
* The parsing stops before @link WordGraph#getSuccessor @endlink reaches the
* nil state or if the complete sequence is read.
*
* @fn WordGraph#canParseString
*
* @brief Test whether an WordGraph can parse a string completely.
*
* @signature bool canParseString(a[, v], str);
*
* @param[in] a The WordGraph to use for parsing.
* @param[in] v Optionally, the descriptor of the vertex to start at. Defaults
* to the root.
* @param[in] str The string to parse.
*
* @return bool <tt>true</tt> if the WordGraph parses <tt>str</tt> , starting at
* <tt>v</tt>, completely and <tt>false</tt> otherwise.
*
* @section Remarks
*
* This has not implemented yet.
*/