Simon Peyton Jones - Linear Haskell: practical linearity in a higher-order polymorphic language

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pyrale · 2020-09 · Recommendation

SPJ usually makes great introductions about new things being introduced to GHC. Here's one about linear types: [VIDEO] > How do people that don't have PhDs bridge the gap in their knowledge from what's commonly taught/used (OOP and it's design patterns) to thinking in terms of monads/monoids/functors/etc. In my own experience, you just practice, and munch new knowledge bits by bits. The crucial point here is that you don't need to know _all_ of haskell to be productive using it. So you learn the basics, start using monads without understanding the Monad abstraction (it's really not something you need to understand to use), and after a while it just clicks. And once you're confortable with this basic knowledge, you learn new things when you need them. As a result, I (and many other paid haskellers) have a job writing haskell without having a PhD, without learning category theory, or without a deep math bagage.

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throwaway17_17 · 2020-03 · Recommendation

Session Types, AFAIU are a specific implementation of a linear logic in some type system and I am not all too familiar with them in practice. However, I would like to think I am well versed in Linear Logic and Substructural Type Theory. I think the works by Wadler are a good place to start, in particular is a sort of review paper, based in intuitionistic logic (which he also covers in said paper), on linear logic. It’s called ‘A Taste of Linear Logic’ (I actually have the paper open in Safari on my iPhone as I type this) and it is written as a sort of primer on the area. Wadler’s bibliographies on the works contained in the pages you linked are a good source as well. If you are at all coming from a place of familiarity with Haskell, a decent overview of the current discussions on Linear Types in functional languages is at [2]. And lastly, if you like videos, Simon Peyton Jones has a great talk on YouTube [3] where he discusses practical linear types for Haskell, but the theory is not Haskell specific. I will warn you that the latter two references make several arguments and then discuss uniqueness typing (which is related but very different) and that is a whole other rabbit hole of sources, but generally a good topic to dig into as well. [1] [LINK] [2] [LINK] [3] [VIDEO]

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T-R · 2018-10 · Recommendation

Something to keep in mind - linear types are on their way[1], with exactly this usecase in mind. Simon Peyton Jones gave an excellent presentation on the topic[2], briefly discussing exceptions, as well as giving a mention to ResourceT and the phantom type solution in the article (described as channel-passing). [1] [LINK] [2] [VIDEO]

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