1. In the src/bin folder, create a file called stdin.rs

2. Add the following code and run it with cargo run --bin stdin:

1   use std::io;
2   use std::io::prelude::*;
3
4   fn main() {
5     print_single_line("Please enter your forename: ");
6     let forename = read_line_iter();
7
8     print_single_line("Please enter your surname: ");
9     let surname = read_line_buffer();
10
11    print_single_line("Please enter your age: ");
12    let age = read_number();
13
14    println!(
15      "Hello, {} year old human named {} {}!",
16      age, forename, surname
17    );
18  }
19
20  fn print_single_line(text: &str) {
21    // We can print lines without adding a newline
22    print!("{}", text);
23    // However, we need to flush stdout afterwards
24    // in order to guarantee that the data actually displays
25    io::stdout().flush().expect("Failed to flush stdout");
26  }
27
28  fn read_line_iter() -> String {
29    let stdin = io::stdin();
30    // Read one line of input iterator-style
31    let input = stdin.lock().lines().next();
32    input
33      .expect("No lines in buffer")
34      .expect("Failed to read line")
35      .trim()
36      .to_string()
37  }
38
39  fn read_line_buffer() -> String {
40    // Read one line of input buffer-style
41    let mut input = String::new();
42    io::stdin()
43      .read_line(&mut input)
44      .expect("Failed to read line");
45    input.trim().to_string()
46  }
47
48  fn read_number() -> i32 {
49    let stdin = io::stdin();
50    loop {
51      // Iterate over all lines that will be inputted
52      for line in stdin.lock().lines() {
53        let input = line.expect("Failed to read line");
54        // Try to convert a string into a number
55        match input.trim().parse::<i32>() {
56          Ok(num) => return num,
57            Err(e) => println!("Failed to read number: {}", e),
58        }
59      }
60    }
61  }