Incremental Compilation?

[Kesanov]

In docs/blog/2017-11-30-parallelism.md you stated that skip is going to have incremental compiler based on memoization:

Although this was a fun hack, the next big exciting change won't involve parallelism, and will take a lot longer than a weekend — it's making the compiler incremental, using Skip's own reactive memoizer to only recompile code affected by modified files. Stay tuned!

But there was no follow up post on this topic, even though it's almost 3 years already. Therefore, I have few questions:

1. Does skip have incremental compiler?
2. How many parts of the compiler are actually incremental?
3. Was builtin meoization useful?
4. If yes, are there also some examples where memoization (perhaps surprisingly) wasn't that useful?

[Kesanov]

Any update @josephsavona.

[josephsavona]

I stopped working on this project in late 2018. IIRC we did have incremental compilation working at that time - cc @pikatchu re the current status.

[Kesanov]

Thank you for your reply. Btw, since the project looks quite dead, are there any lessons-learned worth sharing?

• How well did the ref-counting work in practice. Wasn't it too slow, compared to traditional GC?
• Would you like to see built-in memoization in other languages? Why? What does it give you over a library?

[dumblob]

Raising my hand for lessons learned write-up (preferably an exhaustive one :wink:).