NDC Conferences
6 HN recommenders · recommended in 9 months, 2018–2024
51:40 · 71K views · Jul 5, 2017
Scott Wlaschin's NDC talk on using statically typed functional programming, F# in particular, to model a business domain. Types are used to represent the domain precisely and to encode business rules so that illegal states cannot be built, with the compiler acting as an instant unit test.
HN people recommend it as an eye-opening talk whose domain-modeling ideas carry over to other languages and make a strong compiler feel like a coding partner.
9 comments from Hacker News
If anyone is looking for a really eye-opening video take a look at that this. "Domain Modeling Made Functional" It's applying Functional Programming to plain old Enterprise line of business apps in F#. The author argues why it's so much simpler, and simply walks through an example with cases. It's hard not to be persuaded. It leaves behind all of the lofty crazy maths you see in a lot of presentations of FP, and just shows how it's a simpler technique to solve real world problems. Domain Modeling Made Functional - this video (Watch on 1.25x speed) It's really impressive, and also surprising why more people promoting FP don't show it's tangible benefits and simplicity vs. the theoretical/abstract way it's usually presented. It's also a great introduction to 'Domain Driven Design' and data modeling regardless of the language you use.
The "F# for fun and profit" site by Scott Wlaschin is a great jumping-off point: [LINK] I discovered it when I was reading a lot about domain driven design, and I stumbled upon a talk by the author that kind of blew my mind: "Domain Modeling Made Functional" this video
In re: Haskell's goodness or badness, compare and contrast with, say, PHP (crap language with wild success.) Or Prolog (a stately Elven language with deep but obscure success.) Haskell is what it is. In re: types and data, FP is good for that. See e.g. "Domain Modeling Made Functional" by Scott Wlaschin ( this video ) it's about F# but the concepts apply cross-language. In re: FP PLs "done right" I submit Elm lang. I've been using Elm recently and it gets the job done. It's weird though: on the one hand, as a experienced professional it feels like a toy. The error messages feel almost insulting, like I'm being patronized. On the other hand, once I got over that (silly) reaction, they're awesome. Changing code is a breeze, because Elm leverages the crap out of the type system, and the structure of the code and runtime prevent whole vast categories of errors. Combine that with the sort of Domain-Driven development that Wlaschin is talking about and "baby, you got a stew going!"
Yep! This talk captures it pretty darn well: this video Besides that, the compiler becomes a partner in coding. - Refactoring things is no longer something I avoid, because the compiler will point out any unexpected places that interact with a given piece of code. - I can code for an hour without loading the app, and be reasonably certain that the code I'm writing will be more or less be correct. Overall, I feel like the compiler does the double-checking and second-guessing that I was always doing in the back of my head, which gives some peace of mind and frees me up to focus on the actual task.
I like this talk: "Domain Modeling Made Functional" by Scott Wlaschin this video He's working in F# but the concepts map. There's a fascinating book "Data Model Patterns: A Metadata Map" by David C. Hay that's pretty much a Pattern Language or catalog for data models. You can just implement the subset of Hay's patterns that make sense for your application.