A native interpreter for Elm

on YouTube ↗18m

" summary

Built a native Haskell interpreter that runs Elm programs so a platform can spin up 100k apps and load state from disk, run update, and store it back. It reuses most of the Elm compiler but replaces the optimized AST with a custom AST and interprets it. Major hurdles are JS semantics baked into the standard library and integer-as-double edge cases, so the implementation removes no floats and reimplements native-library behavior for determinism.

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" chapters (13)

1. 0:00Introduction to native Elm interpreter
2. 1:04Elm compiler workflow overview
3. 3:58Changes for blockchain smart contracts
4. 5:23Building a simple Elm interpreter
5. 8:09Adding variables and functions
6. 10:41Pattern matching and case expressions
7. 11:43Custom types and records
8. 12:46Handling negation and edge cases
9. 13:29Challenges with JavaScript compatibility
10. 14:58Runtime errors and debugging tools
11. 15:41Recursion and closures implementation
12. 16:23Open-sourcing the interpreter debate
13. 17:29Future of Elm in new domains

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