Top all-time · #24133
Andy Friesen
Personal blog · andyfriesen.comprogramming
Andy Friesen's personal blog at andyfriesen.com covers programming. Since 2015, 3 different Hacker News readers have linked it 3 times. It is still writing: the last post was on 2026-07-29, and you can follow it by feed.
Too few sampled comments (1) to say how often HN recommends it.?
Why HN links it
One commenter cites this blog's post on testable IO in Haskell as a source for the approach of running business logic in a monad constrained by typeclass capabilities. The comment does not judge the writing.
Summarised by Claude from a sample of 1 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
What Hacker News says?
Sure. I've previously written up a short description of the approach here: http://andyfriesen.com/2015/06/17/testable-io-in-haskell.htm... The general high-level approach is that your business logic functions run in some monad, constrained by the set of capabilities it requires. Each capability is represented as a typeclass. Your type signatures say that your business actions work in every monad that supports those…
Comment linking /2015/06/17/testable-io-in-haskell.html
on “The Evolution of a Haskell Programmer (2001)”Submitted Crux – A Programming Language for People as a story · 3 points
HN discussionSubmitted Haskell Basics: How to Loop as a story · 2 points
HN discussion