Book Image

Rust Standard Library Cookbook

By : Jan Hohenheim, Daniel Durante
Book Image

Rust Standard Library Cookbook

By: Jan Hohenheim, Daniel Durante

Overview of this book

Mozilla’s Rust is gaining much attention with amazing features and a powerful library. This book will take you through varied recipes to teach you how to leverage the Standard library to implement efficient solutions. The book begins with a brief look at the basic modules of the Standard library and collections. From here, the recipes will cover packages that support file/directory handling and interaction through parsing. You will learn about packages related to advanced data structures, error handling, and networking. You will also learn to work with futures and experimental nightly features. The book also covers the most relevant external crates in Rust. By the end of the book, you will be proficient at using the Rust Standard library.
Table of Contents (12 chapters)

How to do it...

  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 }