On Tue, Oct 12, 2010 at 11:09 AM, Rebel Neurofog
<rebelneurofog@gmail.com> wrote:
I've been thinking about Lua string uniqueness and though out of the
optimization could be made:
===============================
static const char *strconst_rgba = "rgba";
static const char *strconst_rgba = "rgb";
static const char *strconst_rgba = "abgr";
static const char *strconst_rgba = "bgr";
static int some_c_function (lua_State *L)
{
if (lua_gettop (L) != 1) return 0;
const char *arg = lua_tostring (L, 1);
/* no 'strcmp ()' here: */
if (arg == strconst_rgba) {
lua_pushnumber (L, 1);
return 1;
} else if (arg == strconst_rgb) {
lua_pushnumber (L, 1);
return 1;
} else if (arg == strconst_abgr) {
lua_pushnumber (L, 1);
return 1;
} else if (arg == strconst_bgr) {
lua_pushnumber (L, 1);
return 1;
}
return 0;
}
int main ()
{
lua_State *L = luaL_newstate ();
assert (lua_loadstrconst (L, strconst_rgba)); /* Check for uniqueness */
assert (lua_loadstrconst (L, strconst_rgb)); /* Check for uniqueness */
assert (lua_loadstrconst (L, strconst_abgr)); /* Check for uniqueness */
assert (lua_loadstrconst (L, strconst_bgr)); /* Check for uniqueness */
/* bind 'some_c_function ()' here */
/* execute some code */
return 0;
}
=======================
The primary idea is to avoid 'strcmp ()'.
Instead we compare pointers (just the way things work inside Lua VM).
What do you think? Is it too mad?
P. S. luaL_checkoption () uses strcmp ()
