Nope, can't do it unless you strip out things that are inherently C++. C++ does too many things "for the programmer's benefit" to allow it to fill the domains that C is good at. They are different languages with different benefits.
It's likely that your idea of what is 'inherent' to C++ is just wrong. First of all, C++ is almost a superset of common C so, yes, it can can really replace C entirely and completely. Whatever grievances you have with the language don't change the reality that even embedded code benefits from, and has been gaining ground in, C++ for quite some time.
In any case, I'm not arguing C++ is inherently 'better' than C. I'm just saying betterunix's assertion that C++ is somehow 'legacy', and C somehow isn't, is weird and illogical.
We do still have a need for a low-level language; C is not the greatest language but it gets the job done. There is also quite a bit of C code out there, proof-of-concept code, reference implementations, etc., and so not knowing C means being cut off from all of that. C++ is not as commonly used for such things, or if it is then only a minimum subset of it is used, and it has no advantage over C as a low-level language. The high-level features of C++ are polluted with low-level concerns that serve as nothing more than a distraction; this has not changed with C++11 and it does not look like it will change with C++14.
So really, the only good reason to be learning C++ in this day and age is if you need to extend or maintain some part of the massive body of already-written C++ code. In other words, if you need to deal with legacy code.
> We do still have a need for a low-level language
C++ can be 'low-level' if that's what you're going to label C. How can you dismiss C++ as not being low-level and then later say it's 'polluted by low-level concerns'?
> There is also quite a bit of C code out there... not knowing C means being cut off from all of that.
I agree. Fortunately, you can't really effectively learn C++ without understanding its C legacy.
> The high-level features of C++ are polluted with low-level concerns that serve as nothing more than a distraction
Until you're working at a high level and need to dig deep and implement a gritty data structure or algorithm with a high-level interface. Sure, you can drop down from Java to C, for example, but then you're in the mud writing JNI bindings. Why do languages have to be constrained to 'high-level' and 'low-level' pigeon holes? Why can't there be room for a language that's good, but perhaps not elegant, slick or beautiful, across the spectrum?
Honestly, I don't want a religious war about it. I just think some of your assumptions are typical of people who have obvious had a bad experience with C++, having used it in a specific context, and therefore think "It didn't work for me, therefore it must be horrible".
On another note, C++ is at least improving and rapidly becoming better tooled, with a growing sense of developer community. C has had a few sprinkles of improvement, but has otherwise reached the end of its natural evolution.
I think C++ is the best procedural, 'high level', statically typed language out there. I also happen to think it's the best portable 'low level' language out there. What would your recommendation be to go alongside C?
I recently (about 2 years ago) started writing, on and off, a new IDE for Clean in C++ with Qt. No complaints. I somehow like it better than C# with all its drag and drop capabilites (yes Qt has that also). However, somehow I like Qts way of doing it better...Don't know what I wanted to say with all this, I just prefer C++ and would choose it for applications. Unless demanded otherwise.
What I said was that C++ has no advantage over C as a low-level language. When you are writing low-level code you usually do not appreciate implicit function calls, extra data being allocated that you did not explicitly declare, name mangling, etc. Low-level C++ code is basically C with a slightly modified set of annoyances balanced by a small set of conveniences.
"Why can't there be room for a language that's good, but perhaps not elegant, slick or beautiful, across the spectrum?"
It is not about being slick and elegant, it is about being productive. The majority of applications are high-level, and the programmers who write those applications get more done when they use high-level languages.
Sure, sometimes an application needs to do a few low-level things. For some high-level languages that means using an FFI (e.g. JNI for Java). We could do better if we wanted; CMUCL and SBCL are Lisp implementations that do a fantastic job of separating high-level and low-level constructs, so that you would never know the low-level features existed if all you wrote was high-level code. With C++, you get something very different: high-level code is tangled up with low-level constructs, issues, and reasoning.
"I just think some of your assumptions are typical of people who have obvious had a bad experience with C++, having used it in a specific context, and therefore think "It didn't work for me, therefore it must be horrible"."
Actually, I switched from C++ to Lisp after having programmed in C++ for more than a decade. This is not a decision I have any serious regrets about. With Lisp I am writing high-level code more easily, and what I am seeing is (a) better performance, (b) the ability to do more ambitious things, and (c) less time spent debugging. Sure, I have bugs in my Lisp code, but those are exclusively high-level bugs -- bugs in logic, bugs that I can fix without having to spend hours tracing pointers. In Lisp, I can report errors anywhere and not have to worry that my program will abort; in C++, sometimes errors just have to go unreported.
It is not that I had one bad experience with C++. I TA'd a data structures course that was taught in C++, and it was a nightmare that left the students with a poor understanding of basic data structures. I have spent countless hours debugging C++ code -- code I wrote, code others wrote, code written by gurus, code that is supposed to solve high-level problems, etc. My group almost missed an important deadline because of the time we had to spend getting C++ code to work. I have worked with people who refuse to even use C++ exceptions because of the all the problems they cause.
Really, I do not mean to rave about Lisp. It is a great language, but there are plenty of other great languages. I liked programming in F#, though I am not an expert in the language. I have seen people switch from C++ to Haskell without ever regretting their decision (including a number of people who said they would prototype their code in Haskell, then rewrite it in C++ when they needed better performance; the rewrites never happened).
"On another note, C++ is at least improving"
I found C++11 to be a disappointment, and C++14 is looking to be more of the same. C++11 contains lots of fixes to problems that are particular to C++, and those fixes introduce as many problems as they solve.
For example, AFAIK you cannot have a naked struct in C++. A struct is a class, and therefore can have methods, thus can have constructor and destructor.
Also, exceptions are a big part of C++ that I don't think you can remove?
If you want simple, obvious separation of data and logic, and you don't want exceptions or name mangling, then C is probably a better choice for that domain.
I like C++, but it is not C and is unlikely that one will ever replace the other in all the domains.
OTOH, if you want to write OO and you like C++, then it is not a bad choice.
I think both are being used to write new systems, so neither is legacy :-)
The "class" keyword and the "struct" keyword differ only in default member visibility. You're free to use the struct keyword. Yes, such structs can have member functions, but they change little except to act as a convenience. A "naked struct" in C++ is called a POD ("Plain Old Data") type, and there are a few rules to ensure your structure meets that definition. The standard library has a type trait to test a class/struct to see if it meets that definition (called std::is_pod).
> For example, constructors, destructors, virtual functions, namespaces.
None of these actually interfere with any use cases or domain that I can think of. Constructors and destructors are insanely valuable features, even if you use nothing else. Functions are not virtual by default and impose no overhead unless used.
> exceptions are a big part of C++ that I don't think you can remove?
You can turn exceptions off at the compiler level. -fno-exceptions in GCC and Clang. RTTI can also be disabled. Disabling both in embedded cases is perfectly reasonable.
> name mangling
extern "C" {} blocks kill name mangling and allow you to export a C API and ABI compatible function.