Speed or security?... Age old question.
> If you use the high level typing stuff coding is a lot more work and requires more thinking, [...] (but) you can even hope for better performance than C by elision of run time checks otherwise considered mandatory, due to proof of correctness from the type system. Expect over 50% of your code to be such proofs in critical software and probably 90% of your brain power to go into constructing them rather than just implementing the algorithm. It's a paradigm shift.
The idea is to formally prove that the code is not doing unexpected things. The process is relatively simple to understand:
First you define the assumptions you make about the program, its execution environment, and the acceptable/expected results of your program. This is known as "formal specification" of the program. It is a critical part. If your specification is wrong, then the whole approach breaks down. However, this part should be much smaller than your whole codebase, and hence you can be extra careful on it.
Next, using this specification, you write proofs showing that the code can not do anything unintended (such as accessing a buffer out of its valid range). The compiler goes through this proofs and checks that everything is provably correct (according to the specification). Then it can generate code without runtime checks that you would otherwise probably implement, because it is sure that certain things cannot happen. As a result, the code may end up being actually faster.
Although a bit involved, the idea should be pretty intuitive. It is exactly what you are doing in your mind when programming. The main differences are:
1. We humans are pretty comfortable working with inexact and/or incomplete specifications. Then some undefined behavior happens, and our programs bug out. For instance, it is very easy for us to think about the division operator as something that always yields a value, ignoring the "division by zero" edge case. Computers are not, and force you to specify what exactly should happen when you encounter such edge cases.
2. We are also pretty bad at exhaustively checking every possibility, whereas computers excel at it. With the help of human-written proofs, obviously (otherwise verifying a program would involve checking every possible input for it, which is obviously intractable).
TL;DR: The tradeoff here is between development and compilation speed versus correctness, which implies improved security and execution speed.
Rust is promising, without a doubt. But it's not yet truly usable in the same sense that C, C++, Java, Python, Haskell, Go and so many other languages are.
Maybe it'll start to get to that point once 1.0 is released, once we see at least some language and library stability, and then perhaps some adoption. But that just hasn't happened yet.
So although early adopters might not get any useful software out of learning Rust at this stage, they might indirectly improve their future Rust code by having a small influence on the direction of the language.
I do, but I do that on Twitter, because, as you've found out, HN will downvote you into oblivion.
> I have just joined this community I am trying to fit in
Ah ha! Sorry, I didn't see that: usually, new users are in green. (also, your account is 163 days old?) If you haven't checked it out, you should check out the community guidelines: http://ycombinator.com/newsguidelines.html
For what it's worth, I am not trying to 'bash [you]'... but I don't think this was a great comment. Try to keep them more substantial here. Different forums are appropriate for different kinds of discourse, and short little comments are generally not taken very well here.
The same happens to "+1", "thanks", and "interesting!" comments. If you can't write more than two sentences, you probably shouldn't post.
Ada has been around since the beginning of the eighties, has and had performance that is near that of C, does not use a garbage collector, provides C linkage, and is far more safe than C.
If you do allow garbage collection, there were many performant and safe alternatives in the 90ies, such as ML.
It's culture as much as performance.
Is Ada less performant than C? I know it has bounds checking, but that can be turned off for "shipped" software. Does it have some features that incur a runtime cost and that can't be disabled?
With all the runtime turned GNAT can/should produce code with in a percent or two as fast as GCC (they share the same backend).
And Ada has a thing called SPARK which is a set of compiler checks to formally verify your code so you can provably turn off those runtime features safely. https://en.wikipedia.org/wiki/RavenSPARK
As you can see from the article (not that you seem to have read any of it), ATS can express C, and optionally prove low-level stuff about it.
execution speed, safety, programmer productivity ← pick any two
C is certainly very much suited for some parts of an SSL implementation e.g. when you need absolute deterministic performance to avoid timing attacks etc. (Although performance should certainly be good enough with modern compilers for most languages, and avoiding side-channel attacks by having deterministic execution time is also possible without resorting to C).
Using the execution speed as an argument for writing the whole thing in C is just wrong. I haven't heard any good arguments as to why a library such as OpenSSL shouldn't be written in Haskell (or say 98% Haskell and 2% C).
Did someone at some point say
"There is 2% of the code that is performance critical and/or needs low-level code for cryptographic reasons so I'll write everything including the network code, command line argument parser, world, dog and kitchen sink in C" ?
You're right. Null pointers are a nuisance in some languages, but other languages have shown that you can remove them and still have just as much of an expressive language (and the compiler can still translate pointers that might be "null" to actual null enabled pointers, so no performance cost). Rust might show that a stronger type system can remove certain raw pointer flaws from the language while still retaining both execution speed and programmer productivity.
Dependent types might mature to the point that you can use them and gain both execution speed, productivity and safety - time will tell.
> Using the execution speed as an argument for writing the >whole thing in C is just wrong. I haven't heard any good >arguments as to why a library such as OpenSSL shouldn't be >written in Haskell (or say 98% Haskell and 2% C).
Did someone at some point say
"There is 2% of the code that is performance critical and/or needs low-level code for cryptographic reasons so I'll write everything including the network code, command line argument parser, world, dog and kitchen sink in C" ?
...
The article makes the argument that, assuming that the whole program needs to be incredibly performant, you can write say 2% of it in verified ATS code, the rest in C-ish ATS code (ie. without proofs).
I guess you can also choose to write 2% verified low-level code, and the rest in a more high level ATS - ATS is a functional language with garbage collection and I presume other high level goodies that functional programmers are used to.
Programs written in C++ aren't necessarily the fastest out there, but they're usually pretty close. They're at least almost always better than what you'd get when using most other languages.
And the same goes for safety. It may not allow you to write bulletproof code, but using modern C++ techniques can go a very long way toward avoiding many common problems with relative ease.
C++ may not be the most productive language for some developers, but it still does quite a good job of offering a wide variety of functionality, reasonably high-level constructs, good library support, and decent tooling.