Learn Rust

categories: hacking

tags: rust log

Description/Summary

Learn Rust programming.

Content

Rust language
main.rs and lib.rs
Copy and Clone in Rust
Rust discussion
Cargo bin
Rustup toolchains
Rust lang entry
Book: Programming Rust
Good blog posts

Rust language

The Little Book of Rust Books

Learn Rust With Entirely Too Many Linked Lists

Understanding and Evolving the Rust Programming Language August 2020

Rust Starter Kit 2020

Video: Pascal Hertleif - Writing Idiomatic Libraries in Rust

Collections:

Rust book: Common Collections
Module std::collections

To get this out of the way: you should probably just use Vec or HashMap. These two collections cover most use cases for generic data storage and processing. They are exceptionally good at doing what they do. All the other collections in the standard library have specific use cases where they are the optimal choice, but these cases are borderline niche in comparison. Even when Vec and HashMap are technically suboptimal, they’re probably a good enough choice to get started.

Rust’s collections can be grouped into four major categories:

Sequences: Vec, VecDeque, LinkedList

Maps: HashMap, BTreeMap

Sets: HashSet, BTreeSet

Misc: BinaryHeap

main.rs and lib.rs

Separation of Concerns for Binary Projects

The responsibilities that remain in the main function after this process should be limited to the following:

Calling the command line parsing logic with the argument values

Setting up any other configuration

Calling a run function in lib.rs

Handling the error if run returns an error

This pattern is about separating concerns: main.rs handles running the program, and lib.rs handles all the logic of the task at hand.

Code example: https://github.com/Aimeedeer/minigrep-rust-practice

Copy and Clone in Rust

What Is Ownership?

This chapter is really good. The stack and heap are well explained.

Clone and Copy for Duplicating Values

Module core::clone

Differs from Copy in that Copy is implicit and extremely inexpensive, while Clone is always explicit and may or may not be expensive. In order to enforce these characteristics, Rust does not allow you to reimplement Copy, but you may reimplement Clone and run arbitrary code.

Blog post: Moves, copies and clones in Rust

Not much new in this post if you’ve already read Rust book.

Rust discussion

ReadRust: Computer Science

Reddit discussion: Opinions about using Rust instead of C in Computer Science courses

Rust weaknesses: This question got a bunch of discussions

Cargo bin

$ ~/.cargo/bin
-bash: /<my_path>/.cargo/bin: is a directory

$ cd ~/.cargo/bin
$ ls
basic-http-server	cargo-generate		diesel			rust-trending		ssmanager
cargo			cargo-make		lighthouse		rustc			ssserver
cargo-add		cargo-miri		makers			rustdoc			ssurl
cargo-casperlabs	cargo-rm		mdbook			rustfmt			wasm-pack
cargo-clippy		cargo-upgrade		mdbook-linkcheck	rustlings		wasm-pack.stamp
cargo-contract		cargo-watch		rls			rustup
cargo-fmt		cargo-web		rust-gdb		simple-http-server
cargo-fuzz		clippy-driver		rust-lldb		sslocal

$ which cargo
/<my_path>/.cargo/bin/cargo

$ ls -lh
total 496760
-rwxr-xr-x   1 aimeez  staff   5.1M Apr 26  2020 basic-http-server
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 cargo
-rwxr-xr-x   1 aimeez  staff   7.1M Sep 14 10:48 cargo-add
-rwxr-xr-x   1 aimeez  staff   1.0M Aug 25 13:56 cargo-casperlabs
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 cargo-clippy
-rwxr-xr-x   1 aimeez  staff   4.6M Nov  6 20:59 cargo-contract
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 cargo-fmt
-rwxr-xr-x   1 aimeez  staff   1.3M May 18 18:52 cargo-fuzz
-rwxr-xr-x   1 aimeez  staff   6.5M Oct 14 14:37 cargo-generate
-rwxr-xr-x   1 aimeez  staff   7.9M Oct 29 13:17 cargo-make
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 cargo-miri
-rwxr-xr-x   1 aimeez  staff   2.0M Sep 14 10:48 cargo-rm
-rwxr-xr-x   1 aimeez  staff   3.5M Sep 14 10:48 cargo-upgrade
-rwxr-xr-x   1 aimeez  staff   2.1M Aug 11 15:20 cargo-watch
-rwxr-xr-x   1 aimeez  staff   9.5M Oct 29 14:52 cargo-web
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 clippy-driver
-rwxr-xr-x   1 aimeez  staff   3.1M Jun 17 12:56 diesel
-rwxr-xr-x   1 aimeez  staff    42M Aug 11 12:46 lighthouse
-rwxr-xr-x   1 aimeez  staff   7.9M Oct 29 13:17 makers
-rwxr-xr-x   1 aimeez  staff    10M Sep 20 11:06 mdbook
-rwxr-xr-x   1 aimeez  staff   9.3M Sep 20 11:09 mdbook-linkcheck
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 rls
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 rust-gdb
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 rust-lldb
-rwxr-xr-x   1 aimeez  staff   6.5M Jun 13 15:51 rust-trending
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 rustc
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 rustdoc
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 rustfmt
-rwxr-xr-x   1 aimeez  staff   2.7M Jul 27 16:43 rustlings
-rwxr-xr-x  12 aimeez  staff   7.1M Jul 27 16:47 rustup
-rwxr-xr-x   1 aimeez  staff   2.6M Aug 11 15:12 simple-http-server
-rwxr-xr-x   1 aimeez  staff   6.1M Jun  8 11:05 sslocal
-rwxr-xr-x   1 aimeez  staff   4.1M Jun  8 11:04 ssmanager
-rwxr-xr-x   1 aimeez  staff   3.9M Jun  8 11:04 ssserver
-rwxr-xr-x   1 aimeez  staff   1.3M Jun  8 11:03 ssurl
-rwxr-xr-x   1 aimeez  staff   7.2M May 23 01:28 wasm-pack
-rw-r--r--   1 aimeez  staff    54B Oct 29 14:21 wasm-pack.stamp

Rustup toolchains

The rustup book

rustup installs rustc, cargo, rustup and other standard tools to Cargo’s bin directory. On Unix it is located at $HOME/.cargo/bin and on Windows at %USERPROFILE%\.cargo\bin. This is the same directory that cargo install will install Rust programs and Cargo plugins.

Toolchains on my mac:

$ ls ~/.rustup/
downloads	settings.toml	toolchains	update-hashes

$ ls ~/.rustup/toolchains/
1.34.2-x86_64-apple-darwin		nightly-2019-10-14-x86_64-apple-darwin	nightly-x86_64-apple-darwin
1.41.0-x86_64-apple-darwin		nightly-2020-03-19-x86_64-apple-darwin	stable-x86_64-apple-darwin
1.43.1-x86_64-apple-darwin		nightly-2020-05-15-x86_64-apple-darwin
1.45.2-x86_64-apple-darwin		nightly-2020-08-23-x86_64-apple-darwin

$ ls ~/.rustup/toolchains/stable-x86_64-apple-darwin/
bin	etc	lib	share

$ ls ~/.rustup/toolchains/stable-x86_64-apple-darwin/bin/
cargo		cargo-fmt	rls		rust-gdbgui	rustc		rustfmt
cargo-clippy	clippy-driver	rust-gdb	rust-lldb	rustdoc

Rust lang entry

EntryPointType

rust/compiler/rustc_codegen_cranelift/src/main_shim.rs

Rustc: #[lang = “start”]

fn lang_start<T: crate::process::Termination + ‘static>(main: fn() -> T, argc: isize, argv: *const *const u8,)

Rustc uses std to create the main() function, with mymain() as one argument, as lang-start for the operating system to start executing.

From Rust playground, we can generate LLVM code from our empty main function:

fn main() {
}

The LLVM code:

; std::rt::lang_start
; Function Attrs: nonlazybind uwtable
define hidden i64 @_ZN3std2rt10lang_start17hd0d6144126b78ac1E(void ()* nonnull %main, i64 %argc, i8** %argv) unnamed_addr #1 !dbg !42 {
start:

Book: Programming Rust

Good blog posts

Rust in Perspective
Safe Systems Programming in Rust
Graydon Hoare’s response on reddit about Rust, Swift and languages
What next? Graydon’s post on people’s question: After memory safety, what do you think is the next big step for compiled languages to take.
Swift
programming languages and empiricism
Programming Models for Distributed Computation
What makes a good REPL? (2017) (vvvvalvalval.github.io)