Effective ML

Jane Street · 30K views · 2016-04-05 · 1:09:24

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Overview

Yaron Minsky of Jane Street gave this talk to Harvard's OCaml-based CS51 class in 2010. It collects advice on being an effective ML programmer in an industrial setting.

On Hacker News

It is the go-to source for the idea of making illegal states unrepresentable through types, with the key moment at 28:02.

Recommended by 2 HN people across 2 months · HN mentions 2018–2021

Topics

Functional programming Programming language design

What people said

jasim · 2018-11 · Strong recommendation
That'll be a great addition to the book. Can I also recommend Yaron Minsky's talk on OCaml, specifically the part where he talks about "making invalid states impossible": [VIDEO] I've found this to be the single most valuable programming technique I've learnt. Richard Feldman dives deeper into the topic with a lot more examples in [LINK]
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chillee · 2018-02 · Recommendation
I guess the closest thing to what you want in Ocaml is modular implicits. [LINK] As far as the tradeoff, my view on types is a bit different than yours, I think. First, a quick note: > specify manually all the types of all the functions This is usually encouraged in OCaml, in the form of a .mli file. I think types can be a lot more than "compiler checked documentation that can also work as basic tests". They allow you to encode invariants that allow the compiler to check more than basic stuff. I thought this video had a good example. [VIDEO]
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marshray · 2021-11 · Reference
"Make illegal states unrepresentable" is usually attributed to Yaron Minsky of Jane Street. This video shows it at 28:02. [LINK] [VIDEO]
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Sources

Video by Jane Street, played through YouTube.

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