I wouldn't know because I've never written anything in Python. How many 100KLOC non-compiler programs would say have been written in Haskell? It would be great if the team behind one of them would write a technical report so we'd at least slowly get to find out if it's actually easier to work with Haskell than with Python, and if so, by how much.

I agree that would be great. I can't help thinking that you're holding Haskell up to a standard to which you do not hold Rust, Go or Julia. Have you asked their proponents for technical reports on Hacker News threads?

It is Haskell that holds itself to a higher standard. Rust, Julia and Go don't make claims that are anywhere as extreme as Haskell's fans (e.g., see on this page the claim that Haskell's high abstractions -- optical profunctors or whatever -- are "load-bearing materials" to other languages' "mud". Rust has presented itself as a safe alternative to C/C++; Go presents itself as a high-performance language with simple concurency (or Java without the JVM); Julia presents itself as a high-performance alternative to Matlab, R or NumPy. But Haskell has sort of painted itself into a corner. Because the approach is so foreign and the learning-curve so steep -- i.e., the adoption cost is high -- if it didn't make outlandish claims (like, if it compiles it works) then no one in industry would consider using it. I don't need to know by how much Go lowers development costs because it makes no claims that it does, so I simply assume that it doesn't. That it is faster than Python, easy to learn in a day or two, and that it compiles down to a native executable -- are all trivial to verify. If you want, all of its claims are supported by plentiful data.

But other than that: yes! It is trivial to verify that Rust indeed fulfills its claims, but it is not trivial to verify that that's enough, namely, that overall, the overall cost of developing in Rust is lower than in C++, which is why I wouldn't switch from C++ to Rust without seeing that at least the costs are comparable. I'm also eagerly waiting for data about Rust's concurrency approach.

I would also tell you this: while I find the pure-functional aesthetically unattractive for interactive programs and am very much impressed by Clojure's and Erlang's approaches to state, and while I've personally written a semi-popular Clojure library, I have expressed skepticism about Clojure's suitability for large-scale projects. How well a language works in big software is something that you simply cannot extrapolate from experience in small projects, and as much as I like Clojure, I have serious doubts about its applicability, and I would not use it to write a large system without the kind of data I expect from Haskell.

But all those languages (Erlang and Clojure included) have social advantages that make this data much more easy to come by: they are used by people who aren't enamored with the language itself, who aren't PL enthusiasts, and are much more goal-oriented. Their judgment stems mostly from how well things work, not how interesting the language is. So articles with pertinent data (maybe not enough to risk a large project, but certainly more than those you find for Haskell) are more abundant.

So I don't need to beg for technical reports as much because 1. no wild claims that aren't supported by data are made, and 2. there's data out there (for Go, Erlang, Clojure) or it's coming (Rust).

I think the simplest solution to all of this is for you to ignore the outlandish claims, or at the very least pay attention only to the claims of senior and respectable Haskell propenents, such as Simons Peyton Jones and Marlow, Don Stewart, Lennart Augustsson, Neil Mitchell etc.. Otherwise you're simply allowing yourself to be gently trolled.

By the way "if it compiles it works" is supposed to be somewhat tongue in cheek, as is "avoid success at all costs".

That's not a solution because my problem isn't with Haskell itself (and I do familiarize myself with the theory when I find it interesting, and I'm well aware that most of the researchers aren't like that), but with the tendency of people in the industry to market things so enthusiastically, that they basically encourage suspension of critical thinking (and this is doubly annoying when what they evangelize isn't something as cheap as a new profiler, but something as expensive as a whole new language with a new, unproven, programming paradigm). Ignoring it wouldn't solve the problem. And in case you think this isn't an actual problem, consider that over-excitement about promises that couldn't be kept has caused at least two "research winters" in CS: one in AI and one in formal methods. The industry started believing its own hype, academia didn't mind the extra funding, but when the industry ended up disappointed, funding dried completely and research slowed to a crawl.

So you think you are singlehandedly saving "the" industry from the insidious promotion of Haskell?

Singlehandedly? Absolutely not. Why, am I the only Haskell skeptic you know? There are more on this page alone. There are even PLT researchers who warn against overselling results in PLT, and especially typed FP.

And we're not saving the industry; the industry as a whole isn't suicidal and will never bet too much money on unproven technologies. The industry isn't so fragile, but research is. Given the amount of money in the industry, even small parts that do bet on unproven tech can cause a funding surge followed by a research winter when the disappointment hits. We're saving Haskell.

If those who adopt Haskell do it with clear vision and not by believing some messianic claims, there would be no great disappointment and no research winter. Nothing is more dangerous to research than wild claims. You need to promise less and deliver more, not the other way around. And because the industry is competitive, it is actually quick to adopt ideas once they show actual significant benefit -- i.e., once they're ready. The industry adopted garbage collection almost overnight; it was almost 40 years after it had been invented, but almost immediately after it's been productized well enough to provide a significant advantage.

If pure-FP is really the way to go in general-purpose programming, eventually the industry will adopt it in some well-productized form. Getting there does require some early adopters, but they're already here and overselling doesn't help to get more good ones. It helps to get precisely those adopters who will end up causing a research winter.

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What bothers me in terms of harm to the industry is the waste caused by people switching from one language to another, rewriting libraries over and over and thinning out the effort. I think we're losing years of progress. But there's really nothing I can do about that because even if I can convince someone that a language that is 1% "better" than another does not justify the effort of porting libraries over, there are already too many languages and platforms around, and there's always the question of, so which few languages should we pick, and why should it be the ones you like and not the ones I like. Haskell actually does not contribute much to this problem because its adoption rate doesn't yet make a dent.