Re: LuaJIT 64 bit integers (was: the purpose of lightuserdata)

[Josh Haberman <jhaberman@...>]

Roberto Ierusalimschy <roberto <at> inf.puc-rio.br> writes:
> > Yes, I shudder to think of explaining that to users.  I was initially
> > very excited to hear your announcement of 64-bit integer support since
> > it's been a stumbling block for adoption of Lua inside Google where we
> > have lots of 64-bit integers floating around, [...]
>
> We have discussed in the list how to compile Lua to use long doubles so
> that regular numbers can represent 64-bit integers. Isn't that enough
> for you?

That's definitely one option; the most obvious downside of that is 
that long double takes up twice the memory of double or int64.

As a separate issue, I have been working on an open-source Lua
extension for Google's Protocol Buffers serialization format (for
which int64 and uint64 are native data types), and I don't want my 
extension to require that Lua was built in a non-standard way.

Josh