Types are like the Weather, Type Systems are like Weathermen - Matthias Felleisen

ClojureTV · 15.9K views · 2016-04-17 · 1:15:19

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Overview

Matthias Felleisen's keynote uses weather prediction as an analogy for type systems, arguing they forecast problems so you can act on them. It draws on his experience developing Typed Racket.

On Hacker News

Referenced in static versus dynamic typing debates, including his remark that Hindley-Milner doesn't really work.

Recommended by 1 HN people across 1 months · HN mentions 2016–2021

Topics

Programming language design Functional programming

What people said

jhck · 2016-07 · Recommendation
Matthias Felleisen, one of the developers of Racket, recently gave a talk about the motivation behind typed Racket; it can be found here: [VIDEO]
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moocowtruck · 2021-02 · Reference
how is static typing lacking evidence? don't we use that in rust to prevent the existence of large swaths of errors vs say C? i know for sure when turning on typescript for some javascript projects at work we found many issues, those all seem like wins? Why when I look at some dynamic languages say for example clojure i see stuff like type annotations in their core libraries, and then spec's to help provide a lot of what a type system can do? do you have maybe a counter argument to this fellow [VIDEO]
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iLemming · 2017-10 · Reference
One thing that was a personal shocker for me to hear, from not just anyone, but Matthias Felleisen himself - "My research group has investigated the topic for almost 3 decades, and we came to the conclusion that Hindley-Millner doesn't really work". I was really baffled. That was at ClojureWest 2016. Here's the talk itself [VIDEO] . That talk is not about Clojure - Felleisen doesn't even use Clojure. That happened before Clojure.spec was announced. I couldn't really figure out what exactly he was talking about. Not until later, when I tried Spec.
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Video by ClojureTV, played through YouTube.

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