src/mrdb.erl

@@ -68,7 +68,6 @@
         , select/2        , select/3
         , select_reverse/2, select_reverse/3
         , select/1
-        , ms/2
         , fold/3            , fold/4        , fold/5
         , fold_reverse/3    , fold_reverse/4, fold_reverse/5
         , rdb_fold/4        , rdb_fold/5
@@ -105,7 +104,6 @@
               , db_ref/0
               , ref_or_tab/0
               , index_position/0
-              , match_pattern/0
               ]).
 
 -include("mnesia_rocksdb.hrl").
@@ -127,9 +125,6 @@
 -type outer() :: non_neg_integer().
 -type retries() :: outer() | {inner(), outer()}.
 
--type matchpat_map() :: #{atom() => _}.
--type match_pattern() :: matchpat_map() | ets:match_pattern().
-
 %% activity type 'ets' makes no sense in this context
 -type mnesia_activity_type() :: transaction
                               | sync_transaction
@@ -1337,55 +1332,6 @@ select_reverse(Tab, Pat, Limit) when Limit == infinity; is_integer(Limit), Limit
 select(Cont) ->
     mrdb_select:select(Cont).
 
-%% @doc Produce a match specification for select(), supporting map-based match patterns
-%%
-%% Using record syntax in match patterns tends to conflict with type checking. This
-%% function offers an alternative approach, drawing on the fact that mnesia_rocksdb
-%% keeps the record name and attribute names readily available as persistent terms.
-%%
-%% When using the map-based representation, the match pattern is built by matching
-%% attribute names to map elements; any attribute not found in the map gets set to '_'.
-%% Thus, ```[{#balance{key = {Acct,'$1'},_='_'},[{'>=','$1',Height}],['$_']}]''' can be
-%% created as ```ms(balance,[{#{key => {Acct,'$1'}},[{'>=','$1',Height}],['$_']}])'''.
-%%
-%% This has the advantage over `ms_transform' that it can handle bound variables
-%% in the match pattern. The function works on all mnesia table types.
-%% @end
--spec ms(ref_or_tab(), [{match_pattern(), [_], [_]}]) -> ets:match_spec().
-ms(Tab, Pat) ->
-    #{ attributes := Attrs
-     , record_name := RecName } = any_tab_props(Tab),
-    [{headpat(RecName, Attrs, Hd), Gs, Body}
-     || {Hd, Gs, Body} <- Pat].
-
-any_tab_props(Tab) ->
-    try mrdb_props(Tab)
-    catch
-        exit:{aborted,{bad_type,_}} ->
-            mnesia_props(Tab)
-    end.
-
-mrdb_props(Tab) ->
-    #{properties := Props} = get_ref(Tab),
-    Props.
-
-mnesia_props(Tab) ->
-    try mnesia_props_(Tab)
-    catch
-        exit:{aborted, _} ->
-            mnesia:abort({bad_type, Tab})
-    end.
-
-mnesia_props_(Tab) ->
-    #{ record_name => mnesia:table_info(Tab, record_name)
-     , attributes  => mnesia:table_info(Tab, attributes) }.
-
-headpat(RecName, Attrs, Hd) when is_map(Hd) ->
-    list_to_tuple([RecName | [maps:get(A, Hd, '_')
-                              || A <- Attrs]]);
-headpat(_, _, Hd) when is_tuple(Hd); is_atom(Hd) ->
-    Hd.
-
 clear_table(Tab) ->
     match_delete(Tab, '_').