[erlang-questions] phash2 portability

[Lukas Larsson]

On Wed, Aug 28, 2019 at 8:45 AM Frans Schneider <fchschneider@REDACTED>
wrote:

> Hi list,
>
> According to the docs, the erlang:phash2/2 will return the same result
> regardless of machine architecture and ERTS version. Does this imply
> that this is still true in case the implementation of a basic type, lets
> say a list or map (#{}), will change in the future? Can I assume that
> calculating a hash for a list will have the same result now and in the
> future?
>

Yes. The way hashing of maps works is that it hashes each k/v pair and then
takes the xor of each of those hashes. Since a series of xor's can be
applied in any order without changing the result, the hash value will
always be the same.


>
> Thanks
>
>
> Frans
>
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