/* Lua only functions */
int luaT_lua_newmetatable(lua_State *L)
{
const char* tname = luaL_checkstring(L, 1);
char module_name[256];
int is_in_module = 0;
is_in_module = luaT_classmodulename(tname, module_name);
lua_settop(L, 5);
luaL_argcheck(L, lua_isnoneornil(L, 2) || lua_isstring(L, 2), 2, "parent class name or nil expected");
luaL_argcheck(L, lua_isnoneornil(L, 3) || lua_isfunction(L, 3), 3, "constructor function or nil expected");
luaL_argcheck(L, lua_isnoneornil(L, 4) || lua_isfunction(L, 4), 4, "destructor function or nil expected");
luaL_argcheck(L, lua_isnoneornil(L, 5) || lua_isfunction(L, 5), 5, "factory function or nil expected");
if(is_in_module)
lua_getglobal(L, module_name);
else
lua_pushglobaltable(L);
if(!lua_istable(L, 6))
luaL_error(L, "while creating metatable %s: bad argument #1 (%s is an invalid module name)", tname, module_name);
/* we first create the new metaclass if we have to */
if(!luaT_pushmetatable(L, tname))
{
/* create the metatable */
lua_newtable(L);
/* registry[name] = metatable */
lua_pushvalue(L, -1);
lua_setfield(L, LUA_REGISTRYINDEX, tname);
/* registry[metatable] = tname */
lua_pushvalue(L, -1);
lua_pushstring(L, tname);
lua_rawset(L, LUA_REGISTRYINDEX);
/* __index handling */
lua_pushcfunction(L, luaT_mt__index);
lua_setfield(L, -2, "__index");
/* __newindex handling */
lua_pushcfunction(L, luaT_mt__newindex);
lua_setfield(L, -2, "__newindex");
/* __typename contains the typename */
lua_pushstring(L, tname);
lua_setfield(L, -2, "__typename");
/* __metatable is self */
lua_pushvalue(L, -1);
lua_setfield(L, -2, "__metatable");
/* by default, __version equals 1 */
lua_pushnumber(L, 1);
lua_setfield(L, -2, "__version");
/* assign default operator functions */
lua_pushcfunction(L, luaT_mt__tostring);
lua_setfield(L, -2, "__tostring");
lua_pushcfunction(L, luaT_mt__add);
lua_setfield(L, -2, "__add");
lua_pushcfunction(L, luaT_mt__sub);
lua_setfield(L, -2, "__sub");
lua_pushcfunction(L, luaT_mt__mul);
lua_setfield(L, -2, "__mul");
lua_pushcfunction(L, luaT_mt__div);
lua_setfield(L, -2, "__div");
lua_pushcfunction(L, luaT_mt__mod);
lua_setfield(L, -2, "__mod");
lua_pushcfunction(L, luaT_mt__pow);
lua_setfield(L, -2, "__pow");
lua_pushcfunction(L, luaT_mt__unm);
lua_setfield(L, -2, "__unm");
lua_pushcfunction(L, luaT_mt__concat);
lua_setfield(L, -2, "__concat");
lua_pushcfunction(L, luaT_mt__len);
lua_setfield(L, -2, "__len");
lua_pushcfunction(L, luaT_mt__eq);
lua_setfield(L, -2, "__eq");
lua_pushcfunction(L, luaT_mt__lt);
lua_setfield(L, -2, "__lt");
lua_pushcfunction(L, luaT_mt__le);
lua_setfield(L, -2, "__le");
lua_pushcfunction(L, luaT_mt__call);
lua_setfield(L, -2, "__call");
}
/* we assign the parent class if necessary */
if(!lua_isnoneornil(L, 2))
{
if(lua_getmetatable(L, -1))
luaL_error(L, "class %s has been already assigned a parent class\n", tname);
else
{
const char* parenttname = luaL_checkstring(L, 2);
if(!luaT_pushmetatable(L, parenttname))
luaL_error(L, "bad argument #2 (invalid parent class name %s)", parenttname);
lua_setmetatable(L, -2);
}
}
/* register the destructor function */
if(!lua_isnoneornil(L, 4))
{
/* does it exists already? */
lua_pushstring(L, "__gc");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_pushstring(L, "__gc");
lua_pushvalue(L, 4);
lua_rawset(L, -3);
}
else
luaL_error(L, "%s has been already assigned a destructor", tname);
}
/* register the factory function */
if(!lua_isnoneornil(L, 5))
{
/* does it exists already? */
lua_pushstring(L, "__factory");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_pushstring(L, "__factory");
lua_pushvalue(L, 5);
lua_rawset(L, -3);
}
else
luaL_error(L, "%s has been already assigned a factory", tname);
}
/******** Constructor table and metatable ********/
lua_pushstring(L, "__constructor");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_newtable(L); /* fancy table */
lua_newtable(L); /* fancy metatable */
lua_pushvalue(L, -3); /* metatable */
lua_setfield(L, -2, "__index"); /* so we can get the methods */
lua_pushcfunction(L, luaT_cmt__newindex);
lua_setfield(L, -2, "__newindex"); /* so we add new methods */
lua_pushcfunction(L, luaT_cmt__call);
lua_setfield(L, -2, "__call"); /* so we can create, we are here for only that */
lua_pushvalue(L, -3);
lua_setfield(L, -2, "__metatable"); /* redirect to metatable with methods */
lua_setmetatable(L, -2); /* constructor metatable is ... this fancy metatable */
/* set metatable[__constructor] = constructor-metatable */
lua_pushstring(L, "__constructor");
lua_pushvalue(L, -2);
lua_rawset(L, -4);
}
/* register the constructor function */
if(!lua_isnoneornil(L, 3))
{
/* get constructor metatable */
lua_getmetatable(L, -1);
/* does it exists already? */
lua_pushstring(L, "__new");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_pushstring(L, "__new");
lua_pushvalue(L, 3);
lua_rawset(L, -3);
/* set "new" in the metatable too */
lua_pushstring(L, "new");
lua_pushvalue(L, 3);
lua_rawset(L, -5);
}
else
luaL_error(L, "%s has been already assigned a constructor", tname);
/* pop constructor metatable */
lua_pop(L, 1);
}
/* module.name = constructor metatable */
lua_setfield(L, 6, luaT_classrootname(tname));
return 1; /* returns the metatable */
}
/* Lua only functions */
int luaT_lua_newmetatable(lua_State *L)
{
const char* tname = luaL_checkstring(L, 1);
const void *id;
lua_settop(L, 5);
luaL_argcheck(L, lua_isnoneornil(L, 2) || lua_isstring(L, 2), 2, "parent class name or nil expected");
luaL_argcheck(L, lua_isnoneornil(L, 3) || lua_isfunction(L, 3), 3, "constructor function or nil expected");
luaL_argcheck(L, lua_isnoneornil(L, 4) || lua_isfunction(L, 4), 4, "destructor function or nil expected");
luaL_argcheck(L, lua_isnoneornil(L, 5) || lua_isfunction(L, 5), 5, "factory function or nil expected");
if(luaT_classmodulename(tname))
lua_getfield(L, LUA_GLOBALSINDEX, luaT_classmodulename(tname));
else
lua_pushvalue(L, LUA_GLOBALSINDEX);
if(!lua_istable(L, 6))
luaL_error(L, "while creating metatable %s: bad ardument #1 (%s is an invalid module name)", tname, luaT_classmodulename(tname));
/* we first create the new metaclass if we have to */
if(!luaT_typename2id(L, tname))
{
/* create the metaclass */
lua_newtable(L);
id = lua_topointer(L, -1); /* id = pointer on metaclass */
/* __index points on itself */
lua_pushvalue(L, -1);
lua_setfield(L, -2, "__index");
/* __typename contains the typename */
lua_pushstring(L, tname);
lua_setfield(L, -2, "__typename");
/* by default, __version equals 1 */
lua_pushnumber(L, 1);
lua_setfield(L, -2, "__version");
/* register in "*torch.id2tname*" registry table
(id -> typename) */
lua_getfield(L, LUA_REGISTRYINDEX, "*torch.id2tname*");
if(lua_isnil(L, -1))
{
lua_pop(L, 1);
lua_newtable(L);
lua_setfield(L, LUA_REGISTRYINDEX, "*torch.id2tname*");
lua_getfield(L, LUA_REGISTRYINDEX, "*torch.id2tname*");
}
lua_pushlightuserdata(L, (void*)id);
lua_pushstring(L, tname);
lua_settable(L, -3);
lua_pop(L, 1);
/* register in "*torch.tname2id*" registry table
(typename -> id) */
lua_getfield(L, LUA_REGISTRYINDEX, "*torch.tname2id*");
if(lua_isnil(L, -1))
{
lua_pop(L, 1);
lua_newtable(L);
lua_setfield(L, LUA_REGISTRYINDEX, "*torch.tname2id*");
lua_getfield(L, LUA_REGISTRYINDEX, "*torch.tname2id*");
}
lua_pushstring(L, tname);
lua_pushlightuserdata(L, (void*)id);
lua_settable(L, -3);
lua_pop(L, 1);
}
/* we retrieve the existing metaclass */
else
{
id = luaT_typename2id(L, tname);
luaT_pushmetaclass(L, id);
}
/* we assign the parent class if necessary */
if(!lua_isnoneornil(L, 2))
{
if(lua_getmetatable(L, -1))
luaL_error(L, "class %s has been already assigned a parent class\n", tname);
else
{
const char* parenttname = luaL_checkstring(L, 2);
luaT_pushmetaclass(L, luaT_typename2id(L, parenttname));
if(lua_isnil(L, -1))
luaL_error(L, "bad argument #2 (invalid parent class name %s)", parenttname);
lua_setmetatable(L, -2);
}
}
/******** root-metatable ********/
/* id is the pointer on the metatable
registry[id] = root-metatable, so try to see if it exists */
lua_pushlightuserdata(L, (void*)id); /* id */
lua_rawget(L, LUA_REGISTRYINDEX);
/* not existing? we create a new one! */
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* remove nil on stack */
lua_newtable(L);
/* __index handling */
lua_pushcfunction(L, luaT_rmt__index);
lua_setfield(L, -2, "__index");
/* __newindex handling */
lua_pushcfunction(L, luaT_rmt__newindex);
lua_setfield(L, -2, "__newindex");
/* __metatable field (point on the metaclass) */
lua_pushvalue(L, -2);
lua_setfield(L, -2, "__metatable");
/* __typename contains the typename */
lua_pushstring(L, tname);
lua_setfield(L, -2, "__typename");
/* operators handling */
#define MT_ADD_OPERATOR(name) \
lua_pushcfunction(L, luaT_rmt__##name); \
lua_setfield(L, -2, "__" #name)
MT_ADD_OPERATOR(tostring);
MT_ADD_OPERATOR(add);
MT_ADD_OPERATOR(sub);
MT_ADD_OPERATOR(mul);
MT_ADD_OPERATOR(div);
MT_ADD_OPERATOR(mod);
MT_ADD_OPERATOR(pow);
MT_ADD_OPERATOR(unm);
MT_ADD_OPERATOR(concat);
MT_ADD_OPERATOR(len);
MT_ADD_OPERATOR(eq);
MT_ADD_OPERATOR(lt);
MT_ADD_OPERATOR(le);
MT_ADD_OPERATOR(call);
/* assign the metaclass as metatable... */
lua_pushvalue(L, -2);
lua_setmetatable(L, -2);
/* id is the pointer on the metatable
set registry[id] = root-metatable */
lua_pushlightuserdata(L, (void*)id); /* id */
lua_pushvalue(L, -2); /* metatable */
lua_rawset(L, LUA_REGISTRYINDEX); /* registry[id] = metatable */
} /* ok, so now we have the root-metatable on the stack */
/* register the destructor function */
if(!lua_isnoneornil(L, 4))
{
/* does it exists already? */
lua_pushstring(L, "__gc");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_pushstring(L, "__gc");
lua_pushvalue(L, 4);
lua_rawset(L, -3);
}
else
luaL_error(L, "%s has been already assigned a destructor", tname);
}
/* register the factory function */
if(!lua_isnoneornil(L, 5))
{
/* does it exists already? */
lua_pushstring(L, "__factory");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_pushstring(L, "__factory");
lua_pushvalue(L, 5);
lua_rawset(L, -3);
}
else
luaL_error(L, "%s has been already assigned a factory", tname);
}
/******** Constructor table and metatable ********/
lua_pushstring(L, "__constructor");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_newtable(L); /* fancy table */
lua_newtable(L); /* fancy metatable */
lua_pushvalue(L, -4); /* metaclass */
lua_setfield(L, -2, "__index"); /* so we can get the methods */
lua_pushcfunction(L, luaT_cmt__newindex);
lua_setfield(L, -2, "__newindex"); /* so we cannot messup */
lua_pushcfunction(L, luaT_cmt__call);
lua_setfield(L, -2, "__call"); /* so we can create */
lua_pushvalue(L, -4);
lua_setfield(L, -2, "__metatable"); /* redirect to metatable with methods */
lua_setmetatable(L, -2); /* metatable is ... the fancy metatable */
/* set root-metatable[__constructor] = constructor-metatable */
lua_pushstring(L, "__constructor");
lua_pushvalue(L, -2);
lua_rawset(L, -4);
}
/* register the constructor function */
if(!lua_isnoneornil(L, 3))
{
/* get constructor metatable */
lua_getmetatable(L, -1);
/* does it exists already? */
lua_pushstring(L, "__new");
lua_rawget(L, -2);
if(lua_isnil(L, -1))
{
lua_pop(L, 1); /* pop nil */
lua_pushstring(L, "__new");
lua_pushvalue(L, 3);
lua_rawset(L, -3);
}
else
luaL_error(L, "%s has been already assigned a constructor", tname);
/* pop constructor metatable */
lua_pop(L, 1);
}
lua_setfield(L, 6, luaT_classrootname(tname)); /* module.name = constructor-metatable */
lua_pop(L, 1); /* pop the root-metatable */
return 1; /* returns the metaclass */
}
