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diff --git a/src/edit_var.erl b/src/edit_var.erl
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+%%%----------------------------------------------------------------------
+%%% File    : edit_var.erl
+%%% Author  : Luke Gorrie <luke@bluetail.com>
+%%% Purpose : Variable management server - transient and persistent
+%%% Created : 21 Jan 2001 by Luke Gorrie <luke@bluetail.com>
+%%%----------------------------------------------------------------------
+
+%%% This module implements "setq"-like variables. But, this seems a bit
+%%% distasteful because of concurrent updates and so on. Maybe there is
+%%% better way to do variables in general (or just program-internal
+%%% variables).
+
+-module(edit_var).
+-author('luke@bluetail.com').
+
+%%-compile(export_all).
+%%-export([Function/Arity, ...]).
+
+-behaviour(gen_server).
+
+%% External exports
+-export([start_link/0]).
+
+-export([lookup/1, lookup/2, set/2, permanent/2, add_to_list/2]).
+
+%% gen_server callbacks
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).
+
+-record(state, {ets, dets}).
+
+%%%----------------------------------------------------------------------
+%%% API
+%%%----------------------------------------------------------------------
+start_link() ->
+    gen_server:start_link({local, edit_var}, edit_var, [], []).
+
+%% Return: Value | undefined
+lookup(Name) ->
+    lookup(Name, undefined).
+
+lookup(Name, Default) ->
+    gen_server:call(?MODULE, {lookup, Name, Default}).
+
+set(Name, Value) ->
+    gen_server:call(?MODULE, {set, Name, Value}).
+
+%% permanent(Name, true | false)
+permanent(Name, Flag) ->
+    gen_server:call(?MODULE, {permanent, Name, Flag}).
+
+add_to_list(Name, Value) ->
+    List = lookup(Name, []),
+    edit_var:set(Name, include(List, Value)).
+
+include([], Value)        -> [Value];
+include([Value|T], Value) -> [Value|T];
+include([H|T], Value)     -> [H|include(T, Value)].
+
+%%%----------------------------------------------------------------------
+%%% Callback functions from gen_server
+%%%----------------------------------------------------------------------
+
+%%----------------------------------------------------------------------
+%% Func: init/1
+%% Returns: {ok, State}          |
+%%          {ok, State, Timeout} |
+%%          ignore               |
+%%          {stop, Reason}
+%%----------------------------------------------------------------------
+init([]) ->
+    Filename = filename:join(os:getenv("HOME"), "edit_var.dets"),
+    Ets = ets:new(edit_mem_var, [set, public, named_table]),
+    {ok, Dets} = dets:open_file(edit_disk_var,
+				[{type, set},
+				 {file, Filename}]),
+    load_file(Dets, Ets),
+    State = #state{ets=Ets,
+		   dets=Dets},
+    {ok, State}.
+
+%%----------------------------------------------------------------------
+%% Func: handle_call/3
+%% Returns: {reply, Reply, State}          |
+%%          {reply, Reply, State, Timeout} |
+%%          {noreply, State}               |
+%%          {noreply, State, Timeout}      |
+%%          {stop, Reason, Reply, State}   | (terminate/2 is called)
+%%          {stop, Reason, State}            (terminate/2 is called)
+%%----------------------------------------------------------------------
+handle_call({lookup, Name, Default}, From, State) ->
+    {reply, do_lookup(State, Name, Default), State};
+
+handle_call({set, Name, Value}, From, State) ->
+    ets:insert(State#state.ets, {Name, Value}),
+    case is_permanent(State, Name) of
+	true ->
+	    dets:insert(State#state.dets, {Name, Value});
+	false ->
+	    ok
+    end,
+    {reply, ok, State};
+
+handle_call({permanent, Name, Flag}, From, State) ->
+    case Flag of
+	false ->
+	    dets:delete(State#state.dets, Name);
+	true ->
+	    dets:insert(State#state.dets, {Name, do_lookup(State, Name)})
+    end,
+    {reply, ok, State}.
+
+%%----------------------------------------------------------------------
+%% Func: handle_cast/2
+%% Returns: {noreply, State}          |
+%%          {noreply, State, Timeout} |
+%%          {stop, Reason, State}            (terminate/2 is called)
+%%----------------------------------------------------------------------
+handle_cast(Msg, State) ->
+    {noreply, State}.
+
+%%----------------------------------------------------------------------
+%% Func: handle_info/2
+%% Returns: {noreply, State}          |
+%%          {noreply, State, Timeout} |
+%%          {stop, Reason, State}            (terminate/2 is called)
+%%----------------------------------------------------------------------
+handle_info(Info, State) ->
+    {noreply, State}.
+
+%%----------------------------------------------------------------------
+%% Func: terminate/2
+%% Purpose: Shutdown the server
+%% Returns: any (ignored by gen_server)
+%%----------------------------------------------------------------------
+terminate(Reason, State) ->
+    ok.
+
+%%----------------------------------------------------------------------
+%% Func: code_change/3
+%% Purpose: Convert process state when code is changed
+%% Returns: {ok, NewState}
+%%----------------------------------------------------------------------
+code_change(OldVsn, State, Extra) ->
+    {ok, State}.
+
+%%%----------------------------------------------------------------------
+%%% Internal functions
+%%%----------------------------------------------------------------------
+
+load_file(Dets, Ets) ->
+    F = fun(X) -> ets:insert(Ets, X) end,
+    dets:traverse(Dets, F).
+
+do_lookup(State, Name) ->
+    do_lookup(State, Name, undefined).
+
+do_lookup(State, Name, Default) ->
+    case ets:lookup(State#state.ets, Name) of
+	[{_, Value}] ->
+	    Value;
+	[] ->
+	    Default
+    end.
+
+is_permanent(State, Name) ->
+    case dets:lookup(State#state.dets, Name) of
+	[] ->
+	    false;
+	_ ->
+	    true
+    end.