Ordered Table API

// mutators
void     Insert      (const KeyType& key, const DataType& data); 
size_t   Remove      (const KeyType& key);
void     Clear       ();                        // make empty

// data retrieval
bool     Retrieve    (const KeyType& key, DataType& data) const;

// locators
Iterator Includes    (const KeyType& key);
Iterator LowerBound  (const KeyType& key);
Iterator UpperBound  (const KeyType& key);

// size operations
bool     Empty       ()   const;
size_t   Size        ()   const;

// plus the usual support system:
//   logical operators ==(), !=()
//   iterator support for bidirectional iterators
//   Big 4: Constructor, Destructor, Copy Constructor, assignment operator