Re: c side package creation

[Philipp Kraus <philipp.kraus@...>]

Hello,

I would like to append a table, so on the exampe, I would like to check if the table "mypackage" exists, use them and next I would like to check to the "mysubpackage" table after that I would like to append the C function.
How can I check if a table & subtable exists and append a new line?

Thanks

Phil


Am 07.12.2012 um 13:59 schrieb Philipp Kraus:

> Thanks for this great explanation, this helps well.
> 
> Phil
> 
> 
> Am 07.12.2012 um 13:37 schrieb Jerome Vuarand:
> 
>> 2012/12/7 Philipp Kraus <philipp.kraus@flashpixx.de>:
>>> I'm using lua_register to register some C function. I can call them in my Lua script. I would like to build packages, something like: mypackage.mysubpackage.myfunction
>>> The functions (functionpointers) read from a DLL, so I know the name of the package, subpackage and the pointer of the function. How can I build the package structure?
>>> Can I add the packagename to the lua_register eg lua_register(L, "package.subpackage.myfunction", funcptr) ?
>> 
>> You cannot use lua_register to create such packages. What you need to
>> do is create a table on the stack, add your functions to that table,
>> and set the table in the globals. For example:
>> 
>> lua_newtable(L);
>>   lua_pushcfunction(L, myfunction_pointer);
>>   lua_setfield(L, -2, "myfunction");
>>   lua_pushcfunction(L, myfunction2_pointer);
>>   lua_setfield(L, -2, "myfunction2");
>> lua_setglobal(L, "mypackage");
>> 
>> If you want sub-packages, you can create sub-tables :
>> 
>> lua_newtable(L);
>>   lua_newtable(L);
>>       lua_pushcfunction(L, myfunction_pointer);
>>       lua_setfield(L, -2, "myfunction");
>>       lua_pushcfunction(L, myfunction2_pointer);
>>       lua_setfield(L, -2, "myfunction2");
>>   lua_setfield(L, -2, "mysubpackage");
>>   lua_newtable(L);
>>       lua_pushcfunction(L, myfunction3_pointer);
>>       lua_setfield(L, -2, "myfunction3");
>>       lua_pushcfunction(L, myfunction4_pointer);
>>       lua_setfield(L, -2, "myfunction4");
>>   lua_setfield(L, -2, "mysubpackage2");
>> lua_setglobal(L, "mypackage");
>> 
>> You can also use helper functions to help you do that, depending on
>> the Lua version you use that would be luaL_register or luaL_setfuncs.
>> 
> 
> 
>