

Fun with time travel: retroactive data structures in Python - puremachinery
https://github.com/csvoss/retroactive

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erdewit
Why not use a bitemporal data model instead, it's cleaner and easier to reason
about.

[https://en.wikipedia.org/wiki/Temporal_database](https://en.wikipedia.org/wiki/Temporal_database)

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leni536
I think it would be the "naive" implementation. For specific data structures
more efficient specific algorithms can be written.

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gergoerdi
You can also do time-travelling control structures:
[https://hackage.haskell.org/package/tardis-0.3.0.0/docs/Cont...](https://hackage.haskell.org/package/tardis-0.3.0.0/docs/Control-
Monad-Tardis.html#g:2)

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bmn_
Perl did time-travelling variables first, namely in 2007:
Positronic::Variables

[https://www.flickr.com/photos/gunnarwolf/1343377956/](https://www.flickr.com/photos/gunnarwolf/1343377956/)

This in the picture is Conway giving the talk.

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pandler
Can anyone give an example of a use case for this?

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Semiapies
I'd be rather curious; this is an interesting concept.

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rem7
why don't you guys stop stalking github.com/csvoss already? Third post of the
day:
[https://news.ycombinator.com/item?id=10117612](https://news.ycombinator.com/item?id=10117612)
[https://news.ycombinator.com/item?id=10114969](https://news.ycombinator.com/item?id=10114969)

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mejari
Not sure I understand the problem. If each submission is interesting in and of
themselves, does it matter if the source is the same?

