class interface P_DICTIONARY[G,K->HASHABLE]

creation
   make
      --  Initialise.


feature(s) from P_CONTAINER
   --  Status

   count: INTEGER
      --  Number of items/keys.

      ensure
         positive: Result >= 0

   is_empty: BOOLEAN
      --  Is the container empty?


   is_readable: BOOLEAN
      --  Is the container currently readable?


   is_writable: BOOLEAN
      --  Is the container currently writable?


   item: G
      --  Current item.

      require
         readable: is_readable;
         not_empty: not is_empty

feature(s) from P_CONTAINER
   --  Update

   reset
      --  Initialise.

      require
         writable: is_writable
      ensure
         done: is_empty

feature(s) from P_CONTAINER
   --  Output

   out: STRING
      --  String representation.

      ensure
         is_copy:  --  new string

feature(s) from P_CONTAINER
   --  Utility

   is_void (x: ANY): BOOLEAN
      --  Void assertion for generic parameters.


feature(s) from P_SEARCHABLE
   --  Search

   key_search (k: K)
      --  Search key and set current item if successful.
      --  is_equal is used to compare keys.

      require
         readable: is_readable

   found: BOOLEAN
      --  Result of key search.


   found_count: INTEGER
      --  Number of items for found key (always 1 for dictionary).


feature(s) from P_TABLE
   --  Status

   key: K
      --  Current key.

      require
         readable: is_readable;
         not_empty: not is_empty

   is_key_writable (k: K): BOOLEAN
      --  Is the key already used?

      require
         valid: not is_void(k)

feature(s) from P_TABLE
   --  Update

   add (it: G; k: K)
      --  Add item and corresponding key.
      --  (key must be available).

      require
         writable: is_writable;
         not_void_key: not is_void(k);
         acceptable_key: is_key_writable(k)
      ensure
         keep_reference:  --  keep copy of item and key.

   replace (it: G)
      --  Replace current item (key unchanged).

      require
         meaningful: not is_empty;
         writable: is_writable
      ensure
         keep_reference:  --  keep copy of item.

   remove
      --  Remove current item and associated key.

      require
         meaningful: not is_empty;
         writable: is_writable

feature(s) from P_TABLE
   --  Conversion

   to_key_list: P_LIST[K]
      --  List of keys.

      ensure
         done: Result.count = count;
         valid: Result /= Void; --  new list generated each time (but real keys)
         is_shallow_copy: 

   to_item_list: P_LIST[G]
      --  List of items.

      ensure
         done: Result.count = count;
         valid: Result /= Void; --  new list generated each time (but real items)
         is_shallow_copy: 

feature(s) from P_DICTIONARY
   make
      --  Initialise.


feature(s) from P_DICTIONARY
   --  from ANY

   copy (other: like Current)
      --  Copy.

      require
         other_not_void: other /= Void
      ensure
         is_equal: is_equal(other)

   is_equal (other: like Current): BOOLEAN
      --  Equality.

      require
         other_not_void: other /= Void
      ensure
         consistent: standard_is_equal(other) implies Result;
         symmetric: Result implies other.is_equal(Current)

invariant
   empty: is_empty = count = 0;

end of P_DICTIONARY[G,K->HASHABLE]