Spex_guy

5 ms·

1.
by Spex_guy 3y ago
> If the type system is uncomputable, then the type system will never be able to resolve all uses of function pointers everywhere. Can you elaborate on what you mean here, and the problems this might cause? Do you mean that some function
2.
by Spex_guy 4y ago
> What kind of tests are these "behavior test"? Snippets of zig code that use language features and then make sure those features did the right thing. You can find them here: https://github.com/ziglang/zig&
3.
by Spex_guy 4y ago
The compiler adds a tag in debug modes, but not in release modes.
4.
by Spex_guy 5y ago
Parsing this out of utf-8 encoding requires no knowledge of unicode or even utf-8. All of the relevant characters (reverse solidus, quotation mark, and control characters) are single byte characters in the ascii subset. These characters c
5.
by Spex_guy 5y ago
The UTF-8 encoding is designed so that this is usually not a problem. If you do a search in a utf-8 encoded byte array for an ascii character, for example, you can never get a false positive. Compound UTF-8 characters always have the most
6.
by Spex_guy 5y ago
I can't comment for all the other people who are posting and voting for those posts, but at least for me Zig has quickly become my language of choice for side projects. Its cross compilation features alone are enough for it to replace
7.
by Spex_guy 5y ago
Hard to say, 1.0 for us comes when everything is fully stable in both the language and standard library, and we believe that it can last at least 20 years without modification. My estimate is at least 5 years from now, possibly more.
8.
by Spex_guy 5y ago
We currently don't advise using the Zig language in production. The compiler has known bugs and even some miscompilations, and we sometimes make breaking changes to the std lib and even the language. However, `zig cc` and `zig c++` a
9.
by Spex_guy 5y ago
Yes, move semantics were added because the language was considered incomplete without them. In particular, because RAII based resources like std::vector could not be relocated without very expensive value copy operations.
10.
by Spex_guy 5y ago
Memory is typed in C++. You must use placement new to imbue memory with a non-POD type, and that memory continues to have that type until its destructor is invoked. This is what allows the optimizer to assume that vtable pointers don&#x27
11.
by Spex_guy 5y ago
Ah interesting, yeah I suppose if we define "RAII" as just "automatically invoked configurable cleanup", there's no actual need to mark the beginning of the lifetime. All you need is to mark the end of the lifetime
12.
by Spex_guy 5y ago
This is a worry, but it's not as bad as you might initially think. The first thing to notice is that even though the "interface pointer" got fatter, the implementation got much leaner, as it no longer contains the vtable. V
13.
by Spex_guy 5y ago
It's true that language specific IRs are more powerful, but that isn't the problem in this example. Interfaces aren't part of Zig at the language level, nor are object lifetimes over which to make the vtables immutable. Hav
14.
by Spex_guy 5y ago
Zig's build model is mostly to combine everything into one compilation unit (from multiple files). Since Zig doesn't have a preprocessor, the compiler can reason about incremental compilation and avoid rebuilding everything for e
15.
by Spex_guy 5y ago
Haha yeah this is a good insight. "Resource Acquisition Is Initialization" actually has nothing to do with resource acquisition or initialization in most peoples' minds, instead people (including me) tend to think of it as &
16.
by Spex_guy 5y ago
That's a fair criticism, I think C++ blurs a lot of lines that make these things difficult to talk about in isolation, and I'm still working on being more rigorous about picking them apart correctly. The very specific complexity
17.
by Spex_guy 5y ago
I don't mean that these things need to manifest in exactly the same way as they do in C++, but analagous features are needed. You're right that rvalue references are not necessary, but some form of move semantics are. When I say
18.
by Spex_guy 5y ago
It depends a lot, but in practice in Zig devirtualization is effectively constant propagation. The compiler needs to see the place where the vtable is created, and follow that to the place where virtual functions are called, ensuring along
19.
by Spex_guy 5y ago
It's unlikely. RAII comes with a surprising amount of complexity. In order to have a reasonably complete language that has RAII and value types, you must also have: - constructors - destructors - overloadable copy assignment operat
20.
by Spex_guy 5y ago
Your instinct is right about array types, semantically in Zig they are passed by value. Parameter values are always const though, which allows the compiler to sometimes use pass-by-const-ref to avoid copying large pieces of data. Since ar
21.
by Spex_guy 5y ago
The process of adding new versions of glibc to the data set is described in the readme. If something changes in a way the format doesn't handle, we can just change it and update the code in the compiler at the same time. The file shi