A C++ 20 module of Rust-like std.

C++’s language features are exciting, but I’m tired of the std.
Made this for coding with C++ easier.

I believe a standalone static-library std can solve many C++ pain points.
It doesn't have to mirror another language's stdlib — it could be designed to fit C++ idioms better.
My time is limited, so I anchored the design on Rust's std.

Require

clang 18+
gcc 15+
windows(clang 22+ with msvc std header)

limitation

Linear Type

C++ has no linear type support, so types like NotNull and Unique cannot be fully enforced.
This project keeps them as part of the API and provides memcpy-like checks for null state.

Choice(match)

No good design for a general Choice interface yet. Option/Result are implemented independently for now and may migrate once a Choice API is designed.

Auto Trait

Could perhaps be done with some C++20 reflection magic, but I plan to wait for C++26.

Progress

Module	Area	Types & APIs
core	types	`Option<T>`, `Result<T,E>`
	traits	`Impl` / `dyn` dispatch, `Clone`, `Copy`, `From` / `Into` / `AsRef` / `AsMut`, `PartialEq` (partial)
	fmt	`Display`, `Debug`, `Formatter`, `format_string`, `Arguments`
	ptr	`NonNull<T>`(just api, no linear type support), `ref<T>`, `mut_ref<T>`, `dyn<Trait>`
	mem	`ManuallyDrop`, `MaybeUninit`
	str	`str`, `CStr`
	num	`NonZero`, integer traits
	sync	`Atomic<T>`, memory ordering
	ops	`FnOnce`, `FnMut`, `Fn`
	misc	`Hash` / `Hasher`, `Duration`, `panic` / `PanicInfo`, `slice` (partial)
alloc	containers	`Box<T>`, `Vec<T>`, `String`, `CString`
	shared ownership	`Rc<T>` / `Weak<T>`, `Arc<T>` / `Weak<T>`
	allocator	`Layout`, `Global`, `alloc` / `dealloc`
std	io	`Read`, `Write`, `Seek`, `BufRead` traits, `BufReader` / `BufWriter`, `Cursor<T>`, `Stdin` / `Stdout` / `Stderr`, `io::Error`, `print` / `println` / `eprint` / `eprintln`
	thread	`spawn`, `sleep`, `park`, `yield_now`, `JoinHandle<T>`, `Builder`, `ThreadId`
	sync	`Mutex<T>` / `MutexGuard`, `mpsc::channel` / `sync_channel`
	process	`Command`, `Child`, `ExitStatus`, `Stdio`, `Output`, `ChildStdin` / `ChildStdout` / `ChildStderr` (impl Read/Write), `abort`, `exit`, `id`
	env	`var`, `set_var`, `remove_var`
	time	`Instant`, `SystemTime`, `Duration`
runtime	defaults	default allocator (`operator new`), panic handler (`rstd_panic_impl`)

Not yet implemented

iter: Iterator / IntoIterator
collections: HashMap, BTreeMap
fs: Path, File, read / write / metadata
net: TcpStream, TcpListener, UdpSocket
sync: RwLock, Condvar, Barrier, Once
async: Future, async / await
os: OsString / OsStr
error: Error trait (defined, not widely used)

Documents

work in progress

Installation

FetchContent_Declare(
  rstd
  GIT_REPOSITORY https://github.com/hypengw/rstd.git
  GIT_TAG master
  # GIT_TAG <commit>
  EXCLUDE_FROM_ALL)
FetchContent_MakeAvailable(rstd)