VIP - add erlang_fields pattern converter

Author: shahryarjb

lib/helper/extra.ex

@@ -38,6 +38,13 @@ defmodule MishkaDeveloperTools.Helper.Extra do
   def erlang_result(:selected), do: [:"$$"]
   def erlang_result(term), do: term
 
+  def erlang_fields(tuple, [], _keys, _num), do: tuple
+
+  def erlang_fields(tuple, [h | t], keys, num) do
+    new_tuple = Tuple.append(tuple, if(h in keys, do: String.to_atom("$#{num}"), else: :_))
+    erlang_fields(new_tuple, t, keys, if(h in keys, do: num + 1, else: num))
+  end
+
   def timestamp() do
     DateTime.utc_now()
     |> DateTime.truncate(:microsecond)

lib/modules/mnesia_assistant/mnesia_assistant.ex

@@ -139,6 +139,8 @@ defmodule MnesiaAssistant do
   defdelegate eg(operation), to: Extra, as: :erlang_guard
 
   defdelegate er(operation), to: Extra, as: :erlang_result
+
+  defdelegate erl_fields(tuple, fields, keys, num), to: Extra, as: :erlang_fields
   ############### Global functions Public Apis ###############
   # Ref: https://www.erlang.org/doc/apps/mnesia/mnesia_chap5#mnesia-event-handling
   # system | activity | {table, table(), simple | detailed}