Statically Typed Interpreters

on YouTube ↗33m

" summary

Builds a statically typed interpreter in Haskell and claims it prevents runtime type errors by moving checks into the compiler stage, using GADTs, existential wrappers to erase and reintroduce type information, and the constraints package’s Dict/dictionary trick to carry typeclass implementations. Implements a small relational-algebra-like DSL, solves scoping and heterogeneous environment issues, and demonstrates evaluation of well-typed ASTs. Not published as open source; used internally while iterating rapidly.

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" chapters (13)

1. 0:00Start
2. 2:27Motivating Problem
3. 4:17Simplified Expression Execution Engine
4. 4:48Tools
5. 5:33Parsing
6. 6:33Binary Operators
7. 9:20Constructors
8. 10:42Logical Operators
9. 11:45Translations
10. 17:52Custom Type Classes
11. 20:20Scoping
12. 21:42Base Case
13. 24:24Sparkle Library

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