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Re: [RUST] [DISCUSS] Changing type of array lengths


What would be the argument for using usize over i64/u64? Is usize 64
bits in Rust when compiling on Windows?
On Fri, Dec 7, 2018 at 9:48 AM Andy Grove <andygrove73@xxxxxxxxx> wrote:
>
> I am in favor of using usize.
>
> Thanks.
>
> On Thu, Dec 6, 2018 at 7:20 PM paddy horan <paddyhoran@xxxxxxxxxxx> wrote:
>
> > All,
> >
> > As part of the PR for ARROW-3347 there was a discussion regarding the type
> > that should be used for anything that measures the length of an array,
> > i.e.  len and capacity.
> >
> > The result of this discussion was that the Rust implementation should
> > switch to using usize as the type for representing len and capacity.  This
> > would mean supporting a way to split larger arrays into smaller array when
> > passing data from one implementation to another.  The exact size of these
> > smaller arrays would depend on the implementation you are passing data to.
> > C++ supports arrays up to size i64, but **all** implementations support
> > lengths up to i32 as specified by the spec.  The full discussion is here:
> > https://github.com/apache/arrow/pull/2858
> >
> > This is not a major change so I’ll push it to 0.13 but I wanted to open up
> > the discussion before making the change, the previous debate was hidden in
> > a PR.  In particular, Andy and Chao are you in favor of this change?
> >
> > Paddy
> >