Learning tasks

Learning tasks

Task: Setup environment

• Create GitHub repository, clone it
• Add folder crates
• Add .gitignore

*.swp
target

Task: Print Hello World

• Install rust compiler, vs code, analyzer
• manual compilation
• cargo new
• cargo run

Exercise: Hello world

• Intsall Rust
• Install VS Code or whatever IDE you prefer
• Install rust-analyzer
• Create a new crate
• run the Hello World

Task: Get input from command line and print it

Hello Foo

let args = std::env::args().collect::<Vec<String>>()
let name = &args[1];
println!("Hello {}", name);

Task: Get two numbers from the command line and do some calculations on them

• Add two numbers in main

let x = 23;
let y = 19;
let sum = x + y;
println!("{x} + {y} = {sum}");

Set type of numbers

let x: u8 = 23;
let y = 19;
let sum = x + y;
println!("{x} + {y} = {sum}");

get two numbers from args and add them together

#![allow(unused)]
fn main() {
let args = std::env::args().collect::<Vec<String>>()
let x = &args[1].parse::<u32>().unwrap();
let y = &args[2].parse::<u32>().except("Oh oh");
}

add protection to args (if , len)

#![allow(unused)]
fn main() {
if args.len() {
    eprintln!("{}", args[0]);
}
}

add protection to number parsing

Exercise: rectangle, circle

• Handle overflow

• Read, Write file with oneliners

Task: Implement file-based counter

• Try to read the content of the file.

• todo! if it succeeds

• If it fails set the deault to 1

• Then replace the todo by reading the file, converting the value to a number, incrementing by 1, writing to file.

Task: Word Count (wc)

• Implement a basic version of the wc (Word Count) command.
• On the command line get the name of a file, count how many rows, words, and bytes are in it.