[Rd] long integer in R?

[blue sky]

On Fri, Feb 12, 2010 at 12:06 PM, Simon Urbanek
<simon.urbanek at r-project.org> wrote:
>
> On Feb 12, 2010, at 12:33 , blue sky wrote:
>
>> R-exts.pdf dosen't list many types that are supported in C++, for example,
>> long. Are there storage.mode corresponds to those extra types?
>>
>
> There are none - that's why they are not listed. As for long: on 32-bit
> platforms (and Win64) int and long are equivalent so you can simply use
> INTSXP. On 64-bit unix platforms (LP64) there is no way to losslessly use it
> (other than raw) but in most applications you can simply use REALSXP as it
> gives you at least 52-bits of precision which its sufficient for most
> applications.

According to ?integer,

"Note that on *almost* all implementations of R the range of
representable integers is restricted to about +/-2*10^9: ‘double’s
can hold much larger integers exactly."

It uses 'almost'. I'm wondering on what platform integer is not
restricted to about +/-2*10^9 so that double's can not hold large
integers exactly?