How to read an integer input from the user in Rust 1.0?

Question

Existing answers I\'ve found are all based on from_str (such as Reading in user input from console once efficiently), but apparently from_str(x) h

Answer 1

If you are looking for a way to read input for the purpose of competitive programming in websites like codechef or codeforces where you do not have access to text_io.

This is not a new way to read rather one mentioned in the above answers, I just modified it to suit my needs.

I use the following macro to read from stdin the different values:

use std::io;

#[allow(unused_macros)]
macro_rules! read {
    ($out:ident as $type:ty) => {
        let mut inner = String::new();
        io::stdin().read_line(&mut inner).expect("A String");
        let $out = inner.trim().parse::<$type>().expect("Parseble");
    };
}

#[allow(unused_macros)]
macro_rules! read_str {
    ($out:ident) => {
        let mut inner = String::new();
        io::stdin().read_line(&mut inner).expect("A String");
        let $out = inner.trim();
    };
}

#[allow(unused_macros)]
macro_rules! read_vec {
    ($out:ident as $type:ty) => {
        let mut inner = String::new();
        io::stdin().read_line(&mut inner).unwrap();
        let $out = inner
            .trim()
            .split_whitespace()
            .map(|s| s.parse::<$type>().unwrap())
            .collect::>();
    };
}

In main

fn main(){
   read!(x as u32);
   read!(y as f64);
   read!(z as char);
   println!("{} {} {}", x, y, z);

   read_vec!(v as u32); // Reads space separated integers and stops when newline is encountered.
   println!("{:?}", v);
}

NOTE: I am no Rust Expert, if you think there is a way to improve it, please let me know. It will help me, Thanks.