I was reading the lifetimes chapter of the Rust book, and I came across this example for a named/explicit lifetime: struct Foo<‘a> { x: &’a i32, } fn main() { let x; // -+ x goes into scope // | { // | let y = &5; // —+ y goes into scope let f … Read more
Just having found Rust and having read the first two chapters of the documentation, I find the approach and the way they defined the language particularly interesting. So I decided to get my fingers wet and started out with Hello world… I did so on Windows 7 x64, btw. fn main() { println!(“Hello, world!”); } … Read more
From the documentation, it’s not clear. In Java you could use the split method like so: “some string 123 ffd”.split(“123”); 6 Answers 6
I’m learning/experimenting with Rust, and in all the elegance that I find in this language, there is one peculiarity that baffles me and seems totally out of place. Rust automatically dereferences pointers when making method calls. I made some tests to determine the exact behaviour: struct X { val: i32 } impl std::ops::Deref for X … Read more
I would like to make a Rust package that contains both a reusable library (where most of the program is implemented), and also an executable that uses it. Assuming I have not confused any semantics in the Rust module system, what should my Cargo.toml file look like? 4 Answers 4
I have a value and I want to store that value and a reference to something inside that value in my own type: struct Thing { count: u32, } struct Combined<‘a>(Thing, &’a u32); fn make_combined<‘a>() -> Combined<‘a> { let thing = Thing { count: 42 }; Combined(thing, &thing.count) } Sometimes, I have a value and … Read more
Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 2 months ago. The community reviewed whether to reopen this question last month and left it closed: Original close reason(s) were … Read more
I’m trying to figure out how to match a String in Rust. I initially tried matching like this, but I figured out Rust cannot implicitly cast from std::string::String to &str. fn main() { let stringthing = String::from(“c”); match stringthing { “a” => println!(“0”), “b” => println!(“1”), “c” => println!(“2”), } } This has the error: … Read more
Note: this question contains deprecated pre-1.0 code! The answer is correct, though. To convert a str to an int in Rust, I can do this: let my_int = from_str::<int>(my_str); The only way I know how to convert a String to an int is to get a slice of it and then use from_str on it … Read more
I am doing the Rust by Example tutorial which has this code snippet: // Vec example let vec1 = vec![1, 2, 3]; let vec2 = vec![4, 5, 6]; // `iter()` for vecs yields `&i32`. Destructure to `i32`. println!(“2 in vec1: {}”, vec1.iter() .any(|&x| x == 2)); // `into_iter()` for vecs yields `i32`. No destructuring required. … Read more
