I'm planning to extend my skill list.
But not sure what to tackle next..

I'm fluent in:
- Pascal
- C
- C++
- C#

I know some:
- Python
- HTML
- ASM

I know almost nothing about:
web development ( I can make a wrbsite, but that's it)

what should I add to my list ?

- Java
- Haskell
- PHP
- ASP.Net
- Ruby
- ---------

any advice ? and why ?
I'm also quite techical in my interests and skills.

Work on improving your Python, or add Ruby. Everybody needs a scripting language or two.

C++ ~= C# ~= Java

Java is still very popular, but I wouldn't want to program in it for a living. Unless I got to use Kotlin.

You might want to branch out to Rust, or D, but they're still not very popular.

Pedro's got some good ideas.

D rules. other languages drool.

Except it's criminally underrated so there's:
- small amounts of tutorials
- tiny amounts of actively supported existing libraries

So... if you love coding, D is a beauty. But you're not going to be able to use tons of existing code which makes you a sad panda. It can bind to C (but you have to make bindings, though there are auto-tools for that), and there's a fork that binds to C++. But again, it's a far cry from using C++ and just importing C code like it's nothing.

The community is very helpful, and VERY smart. One of two devs for D is a world-reknowned author of Modern C++ programming book series.

I'm not necessarily recommending you learn it, but it's worth considering because it has a great many paradigms that you'll learn about and then... wish other more popular languages weren't so crappy. The compile-time function evaluation is to die for. The universal call syntax makes everything beautiful.

I literally "invented" pass-by-name in D and made a proof-of-concept adaption of Allegro 5 for it. Only took me a week or so to learn the fundamentals and apply them.

(Pass-by-name is where you specify each input and destination argument explicitly. You can have unlimited default arguments--not just ones on the end like in C/C++/every-other-language, and you can easily change the order and have huge argument lists without confusion. ala:)

my_function(x: 121, y: 24, color: red, size: big) //OBVIOUS which argument goes to which variable (x=121) without needing intellisense. Also makes WRONG ordered arguments easy to find. You CANNOT accidently set y to x's value without explicitly writing it.
my_function(x: 121, y: 24, size:big )//color is optional and NOT the last argument!
my_function( size:big, x: 121, y: 24 ) //re-order arguments

And it was all compile-time, type-checked, that reduced down to plain, full-speed, C code.

My version also had paired values which I've never seen before.

al_draw(bitmap(taco_bmp), pos(232, 242), tint(255,255,255), rotate(0.3));

al_draw(text("Hello World"), pos(232, 242), tint(255,255,255), rotate(0.3));

Note how pos is a pair of arguments. There's NO WAY to get those inter-changed with the color tinting, or rotating (all of which are optional). al_draw enumerates almost all Allegro 5 drawing functions. Text, bitmaps, rotation, scaling, tinting, etc into one function. Everything looks and feels clean and intuitive. It would be great for a GUI too. (Also note, those are NOT FUNCTION CALLS inside. I'm actually creating plain-old-data structs and filling their values--which is also compile-time like any ordinary stack variable.)

This is also (other than Verilog which I learned it from), only usually available in dynamic languages (read: slow), like Python. So look through that Wiki and compare my version with theirs. They're fairly ugly IMO. (*Apparently C# added it in 4.0! Also apparently Objective-c/Swift SEEMS like it has it but it does not.)

I don't know. I'm just so happy with the language itself. And disappointed in how little commercial support (that's needed for a language to blossem these days).

Anyhow, for a realistic recommendation. Do you know C# in depth? If not, there's tons of generics and stuff to learn. Advanced Python too. Generators are fun. (TM)

I have seen SO MUCH HYPE for functional langauges and SO LITTLE USE for 99.9999% of them. They seem like a huge fad for general programming tasks and only useful for scientists/etc who want to think in terms of functions. Like, if your PROBLEM is functional it makes sense to use a functional language (right tool for the right job) but outside of MATH and SCIENCE most problems are way easier to explain in terms of "steps" (client clicks login THEN adds stuff to cart THEN pays for it).

I did want to explore non-traditional error handling techniques. But I've never made much progress. From what I heard, LISP actually uses "error handlers" instead of exceptions/call-stacks so an error happens then it gets dispatched to a willing/available "handler" and then can continue execution.

Why not give a whack at Malbolge!

Imperative languages (Java, Ruby, Python, C, D) are basically the same with slightly different syntax. Some have garbage collection which can be good and bad.

Java is so close to C++ that it's very easy to transfer. Just know that everything is done is a class structure.

Why not try a different paradigm? Functional (lisp/scheme), logic (prolog), ...

Rust or Haxe because they are cool languages.
From your list: Haskell because it is a functional language and you might learn new concepts!
Don't learn Java, it is currently dying a slow and painful death. For the same reason, don't learn PHP if you want to start web development, learn Node.js/Express or Python/Flask instead.

Apart from HTML and CSS I know (almost)nothing about web programming.
Might be interesting to learn how to write not just a website, but a real application for the web. ( like a shop, or a game that can be played in a browser and over the web).
I'm quite "low level" when it comes to programming, knowing some asm, Pascal , C , C++ etc. I can even find my way around in Embedded software. But I barely touched web development.

On the subject of highly functional languages, Elixir seems all the rage these days. This'll be what I learn next.

Looks really nice; like Ruby, but better suited for concurrent stuff, and without the bloat of MRI.

Elixir runs on the erlang vm, you shouldn't try to compare it to ruby.

Back to the topic. I wouldn't recommend learning Java in depth. If you know C# in depth it will be easy to pick up Java, Java is a simpler language and in my opinion, not that well designed. It's still going to stick around for a long time thanks to enterprise software.

PHP is another language I can't recommend, It's a temporary solution that became way too permanent.

Now for languages I would recommend.

Haskell, it's a (almost) pure functional programming language, quite different from an imperative approach. On top of that it's got a lazy evaluation model. The type system is fairly expressive and strong, allowing highly abstract code while enforcing discipline. Started as a language for academic research but it's more than mature enough now for general application development. It does have a few historical design issues such as the default string type being nothing more than an alias for a linked list of chars (bad for performance).

Rust, a systems programming language with a lot of memory safety features at compile-time and some great features such as its traits and pattern matching. It's ownership model can be quite annoying to learn to work with, but promotes much safer code than C or C++.

Other interesting languages.

Kotlin, seems to mainly target the JVM but also seems to have a better design and less issues than Java. Having some null-safety is already a great perk to me.

F#, it's like C# with extra features and ocaml syntax. Some of its features have been ported to C#.

Clojure, it's a lisp targeting the JVM. I'm not a fan of lisp syntax but I can't deny its simplicity and expressiveness.

Prolog, only because it's a completely different paradigm. Functional programming is getting more popular, logic programming however is not (as far as I'm aware that is). But much like functional programming, learning logic programming can change the way you think and approach problems.

Erlang, it's meant for distributed systems, so you might want to learn it, if that's your thing.

Gah, i was just being silly... lalala

Your example is still horrifying though, because the string allocation is not obvious at all. It also doesn't "make sense" in retrospect. Why wouldn't a garbage collector guarantee that? C# has finalizers without that restriction.

I guess Rust is "better" in that regard because there is no garbage collector. On the other hand the different pointer types are difficult to understand, and you constantly have to think about "ownership" and such. It's like manual memory management except you don't get to decide anymore when and where the delete statement goes and also it's invisible.

Java is a lot better than working on a massive Node app that uses callbacks for everything in 2019. Or having a single package have 1,000 dependencies.

Honestly Java really isn't that bad. It's a solid, cross-platform language with a reliable and extensive ecosystem. I'd take Java over D any day if I want to get work done.

The only reason to use any language is the cost benefit analysis of modifying an existing code base. All projects written without the Crux of a pre-existing code base should be written in C (so as to be compatible with all other languages, should a fool be hired who demands a change arises).

Name another language where that exists in a production codebase. That's the point. Anyone who knows Java KNOWS FACTORIES are used everywhere.