Method MakeMetatable

library/LuaWrapper.cpp:1148–1173

* Make a metatable with most common fields, and an empty table for UPVAL_FIELDTABLE. */

 * Make a metatable with most common fields, and an empty table for UPVAL_FIELDTABLE.
 */
void LuaWrapper::MakeMetatable(lua_State *state, const type_identity *type, const char *kind)
{
    int base = lua_gettop(state);
    lua_newtable(state); // metatable

    lua_pushstring(state, type->getFullName().c_str());
    lua_setfield(state, base+1, "__metatable");

    lua_pushlightuserdata(state, const_cast<type_identity*>(type));
    lua_rawsetp(state, base+1, &DFHACK_IDENTITY_FIELD_TOKEN);

    LookupInTable(state, const_cast<type_identity*>(type), &DFHACK_TYPEID_TABLE_TOKEN);
    if (lua_isnil(state, -1))
    {
        // Copy the string from __metatable if no real type
        lua_pop(state, 1);
        lua_getfield(state, base+1, "__metatable");
    }
    lua_setfield(state, base+1, "_type");

    lua_pushstring(state, kind);
    lua_setfield(state, base+1, "_kind");

    // Create the field table
    lua_newtable(state);
}

/**
 * Enable a metafield by injecting an entry into a UPVAL_FIELDTABLE.