2 HN users recommended this talk1 month2013–2020score 1
Years with an HN recommendation, 2007–2026
Cited as an insider's critique of Scala and of non-incremental compilers, often by people warning others off Scala.
Paul Phillips, a former Scala core contributor, argues after moving a million lines of code that much of what the software industry does is wrong. He critiques Scala and compiler design and calls for better approaches.
“Anyone seriously considering Scala should listen to his talk” (HN, 2015)
5 years ago, Paul Phillips was still a core contributor to Scala. Anyone seriously considering Scala should listen to his talk, titled “We’re doing it all wrong”, and take a look at Policy, his fork of the Scala compiler. [this video] [link] Previous discussion: [link]
Former Scala core contributor's critique, worth hearing before adopting Scala
If you enjoy these types of compiler videos then I would highly recommend the following rants against Scala by Paul Phillips (from TypeSafe and one of the core language contributors). He also talks about wanting to edit abstract syntax trees directly: [this video] [link]
Rant against Scala that also covers editing syntax trees directly
>Edward Kmett is a Haskell evangelist Really? Could you point me to some of his evangelizing? Or did you mean "he uses haskell and is quite happy with it"? Because that isn't the same thing. >inconsistencies that the average programmer will never even realize exist. Do you honestly believe that? [this video] >Scala that only when you leave it's confines do you realize, shit, I miss But the very point Edward makes is that you don't give up those things when you leave scala. You only give up those things if you leave scala for something worse. You could leave for something better, keep all those things, and get tons of important things that you also won't realize you are missing until you get used to them and then try to live without them.
Cited as evidence Scala has inconsistencies average programmers miss
Very True. I'm pretty sure that quote wasn't meant to be a critique of the Groovy language, just an expression of interest in Scala. Yet its brought out every time somebody wants to dismiss Groovy. Compare that quote to this[1] presentation where Paul Phillips lays in to scala for 50 minutes. Even when somebody does criticize their own creation I doubt they mean "Hey everybody, that thing I spent a bunch of time on? Throw it all in the garbage, its pointless". [1] [this video]
Scala core contributor criticizes Scala for 50 minutes
Some context - the lead developer on the Scala Compiler, Paul Phillips, went slightly AWOL last year, and presented the talk "We're doing it all wrong" [this video] [link] He still seems slightly burnt by the whole thing: [link] Other critiques of Scala collections have been made with the Typelevel library [link] which aims to fix these issues. This post, 'Next Steps', seems to have come out of Martin Odersky's response to the situation. I commend him for taking practical and thought out action.
Scala compiler lead's talk explaining his departure and critique
Paul, why do you say it's wrong that Float(Long.max - Int.max) is equal to Float(Long.max)? Float has less than 32 significant binary digits, and Long.max - Int.max has the same MSBs as Long.max. You would need to use Double to see the difference. I'm not sure what implicit conversions/promotions have to do with that - you want a warning or error when going from Long to Float? That would be reasonable. You can even lose significant digits between Int->Float and Long->Double even though they have the same total number of bits, so you could require those to be explicit. (from a slide in [this video] )
Slide on implicit numeric conversions and Float precision
a) Martin Odersky has admitted as much[1]. b) The compiler internals are reportedly a mess[2]--likely due at least in part to the extreme number of different syntax variants. c) I find rule 4.1 in OP interesting ("SHOULD avoid concurrency like the plague it is"). According to Odersky's Coursera course[3], one of the main advantages of functional programming as enabled by Scala is easy, safer concurrency (reduced/absent mutable shared state). Yet here we see a presumably seasoned Scala veteran basically saying that this is a failure and we should avoid concurrency whenever possible because it results in too many bugs. 1. [link] 2. [this video] 3. [link]
Cited as support for Scala compiler internals being messy
Oh damn, I didn't know they were the same person. All I knew about him beforehand is from watching this video[1], but it's weird to read about a person and then find out that they also were the same person that you knew from somewhere else. [1] (How Scala [Typesafe] is doing "everything wrong") [this video]
Really good points. I expect you're right about the expressiveness, although I don't really know exactly what you mean by this. The "buffet of abstractions" available in Scala actually put me off it. For me, there are too many options available to expect to have readable, maintainable code at the end of it all, especially if you work in a team which regularly creates almost wilfully hard-to-comprehend java. This video is 2 years old now, but I think it marked the point when I stopped investigating scala. [this video]
Scala's new compiler (dotty) also tries to go that way (first of all using streaming AST-s for better cache locality). The problem is, that usually this "keep state and just percolate changes" is easier said than done. But we're getting there. See also: [this video] (scalac performance) [this video] (what do we really need from "computing science" to do programming) [link]
Scalac performance and incremental compilation talk
A bit tangential, but - an ex-Scala core contributor's lament about why compilers have to be incremental: [this video] - a Rust core team member talking about responsive compilers: [link] (basically the "low-level" implementation of the talk at the previous link)
Ex-Scala core contributor on why compilers must be incremental
Right, and how well do subtyping and implicits get along? This is the problem, everything and the kitchen sink is tossed into Scala without any consideration for how well things work together because they've let it be a PLT grad students playground. [link] [this video] The Scala community didn't lose one its best core developers for nothing. I mention Clojure and Haskell in the same breath because FP and immutability are what I care about and Scala fails to be a nice functional language.
My sample size is small, but the sentiment mainly comes from this: "Pacific Northwest Scala 2013 We're Doing It All Wrong by Paul Phillips - YouTube" [1] [1] [this video]
This is a thing about Scala which gives me pause: it looks like gazing into the guts of the compiler puts one on a course towards a nervous breakdown. [this video]
What is Scala doing in the same list with Rust, Julia, Nimrod, and C++? You do realize there is a JVM preventing it from being a systems level language, right? Also, you should need no more reason to avoid Scala than this: [this video] If you're interested in Scala, learn Haskell. It's faster, its design is re-enforced with proven mathematical concepts, and it doesn't have the worst syntax ever.
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