Spec Generous Dependent StringSet

Dependent StringSet implementation with efficient sequence access by sequence id.

/*!
 * @class GenerousDependentStringSet Generous Dependent StringSet
 * 
 * @extends DependentStringSet
 * 
 * @headerfile <seqan/sequence.h>
 * 
 * @brief Dependent StringSet implementation with efficient sequence access by
 *        sequence id.
 * 
 * @signature template <typename TString> class StringSet<TString,
 *            Depedent<Generous> >;
 * 
 * @tparam TString The type of the string to store in the string set.
 * 
 * The Generous Dependent StringSet stores pointers to a source set, enabling
 * the user to perform deletions and additions to the set without changing the
 * original source set (See @link DependentStringSet @endlink for further
 * details).
 * 
 * @section Run time and Memory
 * 
 * When a value is removed from the Generous Dependent StringSet, the pointer is
 * simply set to zero. The only exception applies to zero pointers at the end of
 * the pointer array, which are removed by resizing the array step by step. This
 * results into the following run time complexity:
 * 
 * - value() or operator []: amortised O(1)
 * 
 * - getValueById(): O(1)
 * 
 * - removeValueById(): amortised O(1)
 * 
 * The memory consumption is linear to the number of pointers but potentially
 * stores a lot of unneccessary null pointers.
 * 
 * See @link TightDependentStringSet @endlink for a Dependent StringSet
 * implementation with a more memory efficient representation at higher costs
 * for by-id element access.
 * 
 * @section Accessing non-existing entries returns empty string
 * 
 * This also applies for accessing a position behind the last element.
 */