The point being that the way you structure your software in each of those styles is very, very different.
They're all idiomatic C++.... just different idioms.
In fact, thinking about it, thats what it is...
C++ is a multi-idiom language.
That is so complex, it is the only language that I need the language at hand to read someone else's code. Not a library reference, a /language/ reference.
Indeed, I am maintaing one C++ application. This is a wrapper for CEF3 (https://cefbuilds.com/). This is the Chromium browser as a library. I have to support the library and wrapper on two platforms: Linux 64 bit and Windows 64 bit. Note that the usual Windows build uses the Microsoft C++ compiler. But, I am uses mingw. This requires source code edits to compile! I blame the complexity of the language.
Indeed, C++ is so difficult that the shop I work for (which is, by the nature of our product, very conservative) has gone to Java instead.
Given language difficulty, while I hope never to maintain C++ code that makes use of SFINAE, Java's simplicity is misleading.
The language might appear simple, but mastering the whole Java eco-system (JSE, JEE, Spring, embedded, Android, features per JDK version), performance monitoring tools, commercial JDKs and IDEs, isn't that easier either.
Also the reason I argue that those that think Go will be kept simple, just aren't prepared for the eventual mainstream enterprise adoption.
Imagine when IBM or similar, releases their vision of GoEE.
There's everything simple about Java. The semantics of Java are actually pretty simple, at least compared to C++. What's complicated are the monstrosities people build with Java, but those aren't inherent in the language.
Saying that Java is complicated because EE exists is like saying that C is complicated because Linux exists: Complexity can be built atop simplicity. And for some reason, Java is a complexity magnet.
As an example, Java's lifetime rules are much simpler than those of C++. At some point after all references are gone, the object will be garbage collected. Simple. But as a result of this simplicity, you don't know when the finalizer will be called. You can't use it, for example, to flush and close a file, because you don't know when file will be closed. Instead, you need to use try/except/finally, and so you can't add this to an existing class, because it would require code modification from all the users of the class.
Up until Java 8 and lambda functions, functions could not be passed as arguments to other functions. Therefore, the developer needed to make an entirely new classes derived from "Callable". Complexity that came from the simplicity of the language.
C++ has a lot of complexity in the language itself. I won't deny that. What I will argue is that the complexity of the language enables simplicity in programs.
Edit: Lambda statements came in Java 8, not Java 7.
C++'s lifetime rules, on most variables, are this: It's allocated until you say it isn't. Some of the vars might be refcounted or GCed, but with GC you've still got the same problem on your hands as finalizers, and refcounting can't handle cycles. Manual memory management is dramatically more error-prone than finalizers ever were (unless you're using RAII, but that's not entirely idiomatic, and cannot be).
As for functions not being able to be passed as args, that's not simplicity, that's a straight up limitation. What makes a language simple is uniformity, simplicity, and consistency. Java has a good deal more of all of these than C++
Complexity in the language doesn't enable simplicity in programs, though, because now your program has to deal with 6000 different special cases.
In any case, Lisp and Scheme are possibly the simplest languages, and are celebrated for their power, clarity, and the simplicity with which they can express programs.
Good point on limitations vs simplicity. I think that there are different forms of complexity. Some complexity is necessary, due to the nature of the underlying problem. Other complexity is incidental, being due to poor implementations. As an example of essential complexity, C++ has different declarations for stack-based variables and heap-based variables, while Java does not. This is because Java does not allow classes to be declared on the heap, and so it does not need an extra form of declaration. On the other hand, C++ definitely has lots of incidental complexity as well, mostly due to its long history. Having four different constructs for loops is incidental complexity.
I agree that the idioms are what make Java programs be complicated, rather than the language itself. What I'm not sure on is how much those idioms are needed to overcome limitations in the language, and how much they are unnecessary parts of the culture.
Oh, absolutely on Lisp. Lisp/Scheme are amazingly simple, and amazingly powerful. The one downside that I've found is that it doesn't correspond to the hardware as much. Much of C++'s complexity stems from trying to provide as many features as possible while still compiling down to reasonably fast code.
What I mean is that while some amount of RAII is a common idiom in C++, It's rare for a program to use RAII fully, as many C++ idioms conflict with it. Mind, I'm not an expert, so I might be wrong, but that was my understanding. AFAICT, if RAII was used all the time, idomatic C++ would look a lot more like Rust.
It is a very good idea and C++ isn't alone there.
Professional Basic dialects, Turbo Pascal, Delphi, Modula-2, Modula-2+, Modula-3, Ada, D, Rust, Mesa/Cedar all share this idea that you can program at both levels, depending on the needs of the use case.
C++ main issue has always been C's compatibility and the C subculture.
The copy-paste compatibility was necessary to bring C developers over the fence to C++, with minimal changes to their tooling.
So C++ inherited all the flaws and UB from C.
Then many of those kept using C++ as plain C with Classes, which influences many of the design decisions regarding language semantics, specially given backwards compatibility as no one wants to repeat Python's error.
Having said this, although I enjoy playing with template metaprogramming, I hope never have to deal with SFINAE, declpspec and function return arrow syntax in production.
And most of those "flaws" aren't flaws in C: They were deliberate design decisons. Arguably bad ones, yes, but they were made a reason. By C++, most of those decisions didn't have any reasons, or were actively against C++'s goals, if not C.
I know you hate C, but blaming C for C++'s problems is like blaming dogs for the monstrous dog demon that someone made with gene editing. C compatability was a bad idea, but you can't blame C for that. Also, it's overly baroque.
But yeah, I think we can all agree that complex TMP is kinda sucky.
Also that no one just placed such class in the the heap, and it was missed, because no one is actually doing code reviews or making use of static analysis.
Another issue with best practices and ownership are binary libraries. There isn't any sort of control one can have over them, so they are the place where RAII and ownership just goes out of the window.
In any case this is much worse in C than C++, because at least C++ does offer some language tools to deal with it, however there is no rescue from developers using C with a C++ compiler.
> Oh, absolutely on Lisp. Lisp/Scheme are amazingly simple, and amazingly powerful. The one downside that I've found is that it doesn't correspond to the hardware as much.
Actually it can also be an upside, as you see with the adoption of FP patterns in mainstream languages, including C++.
One of the themes at CppCon was exactly hardware heterogeneity and possible C++ abstractions to take advantage of it, while keeping the algorithms high level.
auto deleter = [](unsafe_type* t) { cleanup_unsafe(t); }
std::unique_ptr<unsafe_type, decltype(deleter)> safe(make_unsafe(), deleter);
class safe_wrapper {
public:
safe_wrapper()
: unsafe(make_unsafe()) { }
~safe_wrapper() {
cleanup_unsafe();
}
unsafe_type* operator->() { return unsafe; }
private:
unsafe_type* unsafe;
};
Certainly, when passing ownership back to the binary library, you are relying on it to correctly handle ownership. But so long as the ownership is in one's own code, you can easily add the type safety.
Regarding a stack-based class being accidentally placed on the heap, you can't prevent all errors, you can only make it less likely. I'd argue that it is easier to accidentally forget to call a cleanup function than it is to accidentally place something on the heap. With C++11 and up, any calls to "new" should be regarded with deep suspicion.
True on the FP patterns moving in, and I love them. `std::function` is a joy to work with, especially as compared to either C-style function pointers or inheritance from a "callable" type.
The hardware keeps changing. What Lisp provides is a way to access low-level details when necessary, but with a default mode of operation that is managed (developer-friendly): GC, safety checks, arbitrary precision integers, etc. Like for all languages, a compiler can be told to try more optimizations if you want, and if you are ready to spend a little more work on it. In some implementations, you can extend the primitives known the compiler to emit better assembly code (e.g. https://www.pvk.ca/Blog/2014/08/16/how-to-define-new-intrins...).
Wasn't lambda expressions introduced in Java 8?
While true, have you ever tried to answer Java Puzzles?
These are two different things, platform differences are normally handled by a simple abstraction layer (or ifdefs if you're into masochism).