elua: util module, object system, organization

src/bin/elua/core/module.lua

@@ -2,11 +2,11 @@
 
 local M = {}
 
-local util = select(2, ...)
+local cutil = select(2, ...)
 
 local preload = {
-    ffi  = package.preload["ffi"],
-    util = function() return util end
+    ffi   = package.preload["ffi"],
+    cutil = function() return cutil end
 }
 
 local loaded = {

src/bin/elua/core/util.lua

@@ -0,0 +1,42 @@
+-- elua core utilities used in other modules
+
+local M = {}
+
+M.Object = {
+    __call = function(self, ...)
+        local r = {
+            __index = self, __proto = self, __call = self.__call,
+            __tostring = self.__tostring
+        }
+        setmetatable(r, r)
+        if self.__ctor then self.__ctor(r, ...) end
+        return r
+    end,
+
+    clone = function(self, o)
+        o = o or {}
+        o.__index, o.__proto, o.__call = self, self, self.__call
+        if not o.__tostring then
+            o.__tostring = self.__tostring
+        end
+        setmetatable(o, o)
+        return o
+    end,
+
+    is_a = function(self, base)
+        if self == base then return true end
+        local pt = self.__proto
+        local is = (pt == base)
+        while not is and pt do
+            pt = pt.__proto
+            is = (pt == base)
+        end
+        return is
+    end,
+
+    __tostring = function(self)
+        return ("Object: %s"):format(self.name or "unnamed")
+    end
+}
+
+return M

src/bin/elua/main.c

@@ -202,7 +202,7 @@ struct Main_Data {
     int    status;
 };
 
-const luaL_reg utillib[] = {
+const luaL_reg cutillib[] = {
     { "init_module", init_module },
     { "register_callbacks", register_callbacks },
     { NULL, NULL }
@@ -235,7 +235,7 @@ static int lua_main(lua_State *L) {
     }
     lua_pushcfunction(L, register_require);
     lua_createtable(L, 0, 0);
-    luaL_register(L, NULL, utillib);
+    luaL_register(L, NULL, cutillib);
     lua_call(L, 2, 0);
 
     elua_register_cache(L);

src/bin/elua/modules/elm.lua

@@ -1,4 +1,5 @@
 local ffi = require("ffi")
+local cutil = require("cutil")
 local util = require("util")
 
 local elm, evas
@@ -35,16 +36,16 @@ ffi.cdef [[
 local callbacks = {}
 
 local smart_cb_wrapper = ffi.cast("Evas_Smart_Cb",
-    util.register_callbacks(callbacks))
+    cutil.register_callbacks(callbacks))
 
-util.init_module(function()
+cutil.init_module(function()
     elm, evas = ffi.load("elementary"), ffi.load("evas")
     elm.elm_init(0, nil)
 end, function()
     elm.elm_exit()
 end)
 
-local Evas_Object = {
+local Evas_Object = util.Object:clone {
     resize = function(self, w, h)
         evas.evas_object_resize(self.__o, w, h)
     end,
@@ -78,49 +79,52 @@ local Evas_Object = {
     end
 }
 
-M.Window = function(name, title)
-    local o = setmetatable({
-        __o = elm.elm_win_add(nil, name, 0),
-        resize_object_add = function(self, o)
-            elm.elm_win_resize_object_add(self.__o, o.__o)
-        end
-    }, { __index = Evas_Object })
-    elm.elm_win_title_set(o.__o, title)
-    return o
-end
+M.Window = Evas_Object:clone {
+    __ctor = function(self, name, title)
+        self.__o = elm.elm_win_add(nil, name, 0)
+        elm.elm_win_title_set(self.__o, title)
+    end,
 
-M.Background = function(parent)
-    return setmetatable({
-        __o = elm.elm_bg_add(parent.__o)
-    }, { __index = Evas_Object })
-end
+    resize_object_add = function(self, o)
+        elm.elm_win_resize_object_add(self.__o, o.__o)
+    end
+}
 
-M.Label = function(parent)
-    return setmetatable({
-        __o = elm.elm_label_add(parent.__o),
-        text_set = function(self, label)
-            elm.elm_object_part_text_set(self.__o, nil, label)
-        end
-    }, { __index = Evas_Object })
-end
+M.Background = Evas_Object:clone {
+    __ctor = function(self, parent)
+        self.__o = elm.elm_bg_add(parent.__o)
+    end
+}
 
-M.Button = function(parent)
-    return setmetatable({
-        __o = elm.elm_button_add(parent.__o),
-        text_set = function(self, label)
-            elm.elm_object_part_text_set(self.__o, nil, label)
-        end
-    }, { __index = Evas_Object })
-end
+M.Label = Evas_Object:clone {
+    __ctor = function(self, parent)
+        self.__o = elm.elm_label_add(parent.__o)
+    end,
 
-M.Box = function(parent)
-    return setmetatable({
-        __o = elm.elm_box_add(parent.__o),
-        pack_end = function(self, obj)
-            elm.elm_box_pack_end(self.__o, obj.__o)
-        end
-    }, { __index = Evas_Object })
-end
+    text_set = function(self, label)
+        elm.elm_object_part_text_set(self.__o, nil, label)
+    end
+}
+
+M.Button = Evas_Object:clone {
+    __ctor = function(self, parent)
+        self.__o = elm.elm_button_add(parent.__o)
+    end,
+
+    text_set = function(self, label)
+        elm.elm_object_part_text_set(self.__o, nil, label)
+    end
+}
+
+M.Box = Evas_Object:clone {
+    __ctor = function(self, parent)
+        self.__o = elm.elm_box_add(parent.__o)
+    end,
+
+    pack_end = function(self, obj)
+        elm.elm_box_pack_end(self.__o, obj.__o)
+    end
+}
 
 M.exit = function()
     elm.elm_exit()