input.rs

use std::{io::{self, Write}, str::FromStr};

fn main() {
    let name = input("What's your name? ");
    let number: f64 = input_num("What's your favorite number? ");
    println!("{name}'s favorite number is {number:.2}.");
}

fn input(prompt: &str) -> String {
    let mut line = String::new();
    print!("{prompt}");
    io::stdout().flush().expect("success");
    io::stdin().read_line(&mut line).expect("success");
    String::from(line.trim())
}

fn input_num<T>(prompt: &str) -> T 
where
    T:FromStr + Default
{
    input(prompt).parse().unwrap_or_default()
}