オンライン Rust コンパイラ

fn main() {
    println!("Hello, World!");
}

fn main() {
    let name: &str = "Alice";
    let age: u32 = 30;
    let height: f64 = 5.6;
    let is_student: bool = true;
    println!("{} is {} years old", name, age);
}

fn main() {
    let x = 10;
    if x > 0 {
        println!("Positive");
    } else if x == 0 {
        println!("Zero");
    } else {
        println!("Negative");
    }
}

fn main() {
    for i in 1..=5 {
        println!("Count: {}", i);
    }

    let fruits = ["apple", "banana", "cherry"];
    for fruit in &fruits {
        println!("{}", fruit);
    }
}

fn greet(name: &str, greeting: &str) -> String {
    format!("{}, {}!", greeting, name)
}

fn main() {
    println!("{}", greet("Alice", "Hello"));
    println!("{}", greet("Bob", "Hi"));
}

use std::collections::HashMap;

fn main() {
    let mut fruits = vec!["apple", "banana", "cherry"];
    fruits.push("date");
    println!("{}", fruits[1]);

    let mut person = HashMap::new();
    person.insert("name", "Alice");
    println!("{}", person["name"]);
}

struct Dog {
    name: String,
    breed: String,
}

impl Dog {
    fn new(name: &str, breed: &str) -> Self {
        Dog { name: name.to_string(), breed: breed.to_string() }
    }
    fn bark(&self) -> String {
        format!("{} says Woof!", self.name)
    }
}

fn main() {
    let dog = Dog::new("Rex", "Labrador");
    println!("{}", dog.bark());
}

use std::num::ParseIntError;

fn parse_number(s: &str) -> Result<i32, ParseIntError> {
    s.trim().parse()
}

fn main() {
    match parse_number("not a number") {
        Ok(n) => println!("Parsed: {}", n),
        Err(e) => println!("Error: {}", e),
    }
}

use std::fs;
use std::io::Write;

fn main() {
    let mut file = fs::File::create("output.txt").unwrap();
    file.write_all(b"Hello, File!").unwrap();

    let content = fs::read_to_string("output.txt").unwrap();
    println!("{}", content);
}

fn take_ownership(s: String) -> String {
    println!("Got: {}", s);
    s
}

fn borrow(s: &str) -> usize {
    s.len()
}

fn main() {
    let s1 = String::from("hello");
    let s2 = take_ownership(s1);
    let len = borrow(&s2);
    println!("{} has {} chars", s2, len);
}