anchor.diff:  
   %% @doc Reads a schema definition with the same key as `Key' from the internal
   %% storage. If there is no such key in the storage, an exception will be thrown.
  --spec read_schema(Key :: any()) -> jesse:json_term() | no_return().
  -read_schema(Key) ->
  +-spec read(Key :: any()) -> jesse:json_term() | no_return().
  +read(Key) ->
     case ets:lookup(table_name(), Key) of
       [{Key, _SecondaryKey, _TimeStamp, Term}] ->
         Term;
  
positive.code: -module(jesse_database).
  
  %% API
  -export([ add_schema/3
          , del_schema/1
          , read_schema/1
          , update/4
          ]).
  
  
negative.code: %% @doc Adds a schema definition `Schema' to in-memory storage associated with
  %% a key `Key'. It will overwrite an existing schema with the same key if
  %% there is any.
  -spec add( Schema        :: jesse:json_term()
           , ValidationFun :: fun((any()) -> boolean())
           , MakeKeyFun    :: fun((jesse:json_term()) -> any())
           ) -> update_result().
  add(Schema, ValidationFun, MakeKeyFun) ->
    store_schema([{"", "", Schema}], ValidationFun, MakeKeyFun).
  
  %% @doc Deletes a schema definition from in-memory storage associated with
  %% the key `Key'.
  -spec delete(Key :: any()) -> ok.
  delete(Key) ->
    Table = table_name(),
    ets:delete(Table, Key),
    ok.
  