steveklabnik/number_game.md

## number_game.md

      
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              number_game.md
            
          
    Help the docs!

EDIT: If you read the gist before, I've updated it with my latest version. I'm pretty sure I took care of everyone's comments, thanks so much!
So! The new tutorial will be focused on building several small projects in Rust. This example is the first one: a classic 'guessing game.' This was one of the first programs I wrote when I first learned C. 😄
I'd like the feedback of the community before I actually start writing the guide. So this code will be the final code of the first real example Rust programmers see. So I want it to be good. I don't claim this code is good, I just worked something out real quick. Oh, and this is tracking master.
The idea is that I will slowly build from hello world to this final code in steps, introducing one concept at a time. Here are the concepts I'd like a Rust programmer to understand by the time they're done:
Concepts


If
Functions

return (wrt semicolons)


comments
Testing
attributes
stability markers
Crates and Modules
visibility
Compound Data Types
Tuples
Structs
Enums
Match
Looping
for
while
loop
break/continue
iterators


## number_game.rs
use std::io;
use std::rand::Rng;

fn main() {
    println!("Guess the number!");

    let secret_number = std::rand::task_rng().gen_range(1i, 101);
    println!("Secret number is {}", secret_number);

    let mut guesses: int = 0;
    let mut reader = io::stdin();

    loop {
        println!("Please input guess number {}", guesses + 1);

        let input = reader.read_line().ok().expect("Failed to read line");
        let input_num = from_str::<int>(input.as_slice().trim());

        let num = match input_num  {
            Some(num) => num,
            None      => {
                println!("Please input a number.");
                continue;
            }
        };

        println!("You guessed: {}", num);
        guesses += 1;

        match num.cmp(&secret_number) {
            Less    => println!("Too small!"),
            Greater => println!("Too big!"),
            Equal   => {
                println!("You win!");
                break;
            },
        }
    }

    println!("You took {} guesses!", guesses);
}
	use std::io;
	use std::rand::Rng;

	fn main() {
	println!("Guess the number!");

	let secret_number = std::rand::task_rng().gen_range(1i, 101);
	println!("Secret number is {}", secret_number);

	let mut guesses: int = 0;
	let mut reader = io::stdin();

	loop {
	println!("Please input guess number {}", guesses + 1);

	let input = reader.read_line().ok().expect("Failed to read line");
	let input_num = from_str::<int>(input.as_slice().trim());

	let num = match input_num {
	Some(num) => num,
	None => {
	println!("Please input a number.");
	continue;
	}
	};

	println!("You guessed: {}", num);
	guesses += 1;

	match num.cmp(&secret_number) {
	Less => println!("Too small!"),
	Greater => println!("Too big!"),
	Equal => {
	println!("You win!");
	break;
	},
	}
	}

	println!("You took {} guesses!", guesses);
	}