Python, Ruby, Javascript, JVM-hosted languages like Clojure, Scala, and newer languages still in development like Elixir, I'm sure I'm missing some. Haskell is perpetually 10 years ahead in programming research but sadly it functionally lacks support for day-to-day scripting tasks.

Javascript? Really?

"Thought leaders" are hopefully just using the best language suited for the job. It often comes down to what kind of code you are writing and what it needs to run on.

You're doubting that Javascript is a popular language for people pushing the forefront of software development? I'd cite for you a ton of the work being done on node, ember, knockout, backbone, jquery, even some embeddable hardware thing I read about on here the other day. There's a huge amount of energy in that area, lots of extremely smart people.

Or are you just being snobbish about javascript? It's a pretty solid language, and has interpreters installed on virtually every computer on earth with built-in distribution.

My friend, JS has a virtual monopoly on what it does. If there are other client-side browser languages, i have not heard of them.

>It has built-in interpreters (read "Browsers") on every computer.

JS is pretty slow (It uses an interpreter!). The notion of using it on the backend is debatable. "A lot of people are putting a lot of effort in to it" isn't a valid argument. u said it yourself: "people are told to/forced to use it"

As for the hardware thing, didn't you read the HN discussion about that? no body thinks that's a good idea. It just a way to let web devs do something on the hardware without bothering to learn an actual low level language.

>> JS is pretty slow (It uses an interpreter!) The notion of using it on the backend is debatable.

It is pretty fast. It has a world class VM with an optimising JIT compiler. V8 is considerably faster than many other interpreted language, Ruby, Python etc. It's being used on the backend by many smart companies.

>> As for the hardware thing [...] It just a way to let web devs do something on the hardware without bothering to learn an actual low level language.

I know C. I use it when necessary but I'd rather write JS. Apparently so would plenty of other people. It's not about laziness.

Expect it doesn't use an interpreter these days, it is JIT compiled (a la V8). It's quite fast now.

Is it still single-threaded only using one CPU core?

Well almost, you can use web workers and create "tasks" that will use more cpu cores. https://developer.mozilla.org/en-US/docs/Web/Guide/Performan...

"It's a pretty solid language" - can you remind me what should I use "==" or "===" and why should I care? More here: http://wtfjs.com

"has interpreters installed on virtually every computer on earth with built-in distribution" - which means we are stuck with it, thanks very much for "open" web.

"pushing the forefront of software development" - you mean desperately trying to work around legacy issues in a increasingly standardised environment?

JS is, in general, a relatively poorly designed language which is forced upon us (thankfully, not me). Given the choice people would jump ship in a heartbeat.

Indeed, when compare Java with Python, Ruby, Javascript using the tool that the OP used for showing that monthly commits to Java were stable for the last 7 years it shows how quickly they are catching up:

http://www.ohloh.net/languages/compare?l0=java&l1=javascript...

Although it looks like Ruby isn't growing as quickly as JavaScript and Python.

It will be interesting to see if perceptions change after JavaScript and Python overtake Java.

Ah, knew I'd forgotten one - Go, pretty interesting language with lots of action around it.

Rust, Erlang?

Mostly English. In ridiculous quantities.

I miss thought leaders using French, or Latin :-(

Haskell?

Haskell has multiple concepts that are so compelling that I do not understand why most of the new languages make no use of them. Very handwavy, here are a couple of them.

- Type inference: strong typing at the convenience of weak typing. (Some languages are moving towards this. C++ stapled on `auto` keywords, Rust is designed using it)

- Type classes: unifying things that "can do X", allowing the programmer to write functions that do similar things but work on many different types. A "sort" function can then be written for all things that "are containers of elements that can be compared". (Again, Rust adopts this.)

- Allowing separation of pure and impure functions. Imagine having a "pure" keyword that guarantees that a function doesn't have side effects. The benefit of this cannot be overstated in a multithreaded environment.

C# has had type inference for a long while. It's a pain using Java, which doesn't.

C# also sort of implements type classes. For your example, there's IComparable in C#; implement it and a List<SomeObject> can be directly sorted.

For pure functions, there's the [Pure] attribute, but it isn't enforced by the compiler, it's just a contract, a promise.

Yes, there are languages that also have these features, the puzzling part is why not all of them do (except those that may have good design reasons not to).

Its hard to implement type inference and type classes unless you carefully design the language to accommodate it from day 1. For example, return-type polymorphism (functions like `read` or `return`) is particularly tricky, specially in the more dynamic languages.

"- Type classes: unifying things that "can do X", allowing the programmer to write functions that do similar things but work on many different types. A "sort" function can then be written for all things that "are containers of elements that can be compared". (Again, Rust adopts this.)"

This is what templates do in C++.