Re[2]: using 'uint64_t' with Alien

[Bulat Ziganshin <bulat.ziganshin@...>]

Hello Fabio,

Thursday, July 9, 2009, 9:13:13 AM, you wrote:

LGMP implements unbounded integers. it is somewhat overkill for 64-bit
integers that have more efficient representation

> Phoenix,

> I just found out about LGMP
> (http://members.chello.nl/~w.couwenberg/lgmp.htm), I think it is a
> nice solution for representing 64-bit integers in Lua if you want to
> hack something up quickly, as it has both arithmetic and bitwise ops
> if you want to hack something up quickly. If you want to do it by
> modifying Alien I suggest you check out the head at
> http://github.com/mascarenhas/alien/tree/master, as I did some
> refactoring of Alien's code that makes adding new types a little
> easier.

> The way I will do it for Alien when I get around to implemeting this,
> though, is to use a 64-bit long userdata, and have bitops as methods
> of this userdata's __index metamethod (plus conversion to and from
> strings, and arithmetic/relational metamethods, of course).

> --
> Fabio Mascarenhas

> On Thu, Jul 9, 2009 at 2:12 AM, Fabio
> Mascarenhas<mascarenhas@gmail.com> wrote:
>> Phoenix,
>>
>> I just found out about LGMP
>> (http://members.chello.nl/~w.couwenberg/lgmp.htm), I think it is a
>> nice solution for representing 64-bit integers in Lua if you want to
>> hack something up quickly, as it has both arithmetic and bitwise ops
>> if you want to hack something up quickly. If you want to do it by
>> modifying Alien I suggest you check out the head at
>> http://github.com/mascarenhas/alien/tree/master, as I did some
>> refactoring of Alien's code that makes adding new types a little
>> easier.
>>
>> The way I will do it for Alien when I get around to implemeting this,
>> though, is to use a 64-bit long userdata, and have bitops as methods
>> of this userdata's __index metamethod (plus conversion to and from
>> strings, and arithmetic/relational metamethods, of course).
>>
>> --
>> Fabio Mascarenhas
>>
>>
>>
>> On Thu, Jul 9, 2009 at 12:54 AM, Phoenix Sol<phoenix@burninglabs.com> wrote:
>>> Sigh; I was ignorantly hoping that these things could be 'implicitly
>>> converted' on the C side.
>>> ( Though not very optimistic about the result of doing so. )
>>>
>>> I really need to make the time to learn C; which shall I give up: sleeping,
>>> eating, or my children?
>>> ( I've already given up entertainment, social life, and sex. )
>>>
>>> Phoenix Sol
>>>
>>>
>>> On Wed, Jul 8, 2009 at 10:29 PM, Sam Roberts <vieuxtech@gmail.com> wrote:
>>>>
>>>> On Wed, Jul 8, 2009 at 8:05 PM, Phoenix Sol<phoenix@burninglabs.com>
>>>> wrote:
>>>> > Thanks, Sam.
>>>> >
>>>> > I tried doing this:
>>>> >   tyr.tcrdbrnum:types('double', 'pointer')  --( that's return type, arg
>>>> > type(s), in case you don't speak Alien ) ( and Alien will try to convert
>>>>
>>>> I'd never heard of alien before this post. It doesn't surprise me the
>>>> things you tried failed. You have to tell alien the truth about the C
>>>> API, it won't be able to magically figure out what you want it to do.
>>>>
>>>> I'd talk to Fabio, I think he could modify Alien (or you could) pretty
>>>> trivially so that it used decimal strings on the lua side for
>>>> (u)int64s on the C side. Without that, you aren't going to be able to
>>>> use Alien, I don't think.
>>>>
>>>> Sam
>>>
>>>
>>



-- 
Best regards,
 Bulat                            mailto:Bulat.Ziganshin@gmail.com