Rust 101 (2017 edition)

Introduction to

Rust (Programming Language)

Robert “Bob” Reyes08 Sep 2017

#MozillaPH

#RustPH

#MozillaPH

#RustPH

If you’re on social media, please use

our official hashtags for this talk.

About Me

• Mozilla Rep for the PHL since 2011

• Technopreneur at TurfSitePH.net

• Technology Columnist at MB.com.ph

• Team Manager at SIPFC.org

• Dad of Xeon & Haswell

Being an Open Source Dev

Target Audience

• People with some background in programming (any language).

• People with zero or near-zero knowledge about Rust (Programming Language).

• People who wants to learn a new programming language.

Agenda

• Mozilla in the Philippines

• Installing Rust

• Hello World, the Rust way

• Intro to Cargo

• IDE Support

• Variables & Constants

• Simple Arithmetic Functions

What is

Mozilla?

#MozillaPH

History of Mozilla

On 23 Feb 1998, Netscape Communications Corp.

created a project called Mozilla (Mosaic + Godzilla).

Mozilla was launched 31 Mar 1998.

We have a NEW brand identity…

We have a NEW brand identity…

The

Mozilla Manifesto

Mozilla’s Mission

To ensure the Internetis a global public resource, open & accessible to all.

Get involved …

Some stuff that we are working on …

#MozillaPH

#MozillaPH

How to be part of

MozillaPH?

Areas of Contribution

Helping Users (Support)

Testing & QA

Coding

Marketing

Translation & Localization

Web Development

Firefox Marketplace

Add-ons

Visual Design

Documentation & Writing

Education

Rust Development

http://join.mozillaph.org

Join MozillaPH now!

http://join.mozillaph.org

Internship

at Mozilla

https://careers.mozilla.org/university/

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

Mozilla HQ

#MozillaPH

What is

Rust?

What is Rust?

• Rust is a systems programming language that runs blazingly fast, prevents segfaults, & guarantees thread safety.

• Compiles to Native Code like C++ & D.

• Strength includes memory safety & correctness (just like in C).

“Rust is a modern native-code language with a focus on safety.”

What is Rust?

• At present…

• Rust has more than 6.8K libraries, with more than 85M downloads at crates.io

• More than 40 companies publically using in production (Friends of Rust).

Mozilla &

Rust?

Mozilla ❤️ Rust

• Started as Mozillian Graydon Hoare’s side project.

• He began working on Rust full time in 2009.

• Rust 1.0 released in 2015.

• New releases every six (06) weeks.

• Rust is Mozilla-supported, rather than Mozilla-owned.

Rust & Servo

Rust & Servo

• One part of Mozilla is working on improving Rust.

• Another part is building a brand new web rendering engine using Rust: Servo.

• High-level goals of Servo:

• Implement parallel layout.

• Experiment with alternative rendering design.

• Investigate feasibility of complete JS GC integration.

• Incubator for experiments that can be reintegrated into Firefox.

Rust & Firefox

Rust & Firefox

• We are already shipping Rust code in Firefox (inside the media stack).

• The process of re-writing existing C++ code to Rust is called Oxidation.

• Some of the most challenging projects related to Oxidation is part of the Quantum project.

• The amount of Rust code in Firefox will increase over time.

Rust & Firefox

Why

Rust?

Why Rust?

• Rust solves two core problems from C++ & similar low-level programming languages:

• Data races in multithreaded code.

• Use-after-free (UAF) errors.

• UAF’s are huge source of security exploits in Firefox & other browsers.

• Both problems are addressed by making “ownership” explicit.

Top 10 IoT Programming

Languages

1. C Language

2. C++

3. Python

4. Java

5. JavaScript

6. Rust

7. Go

8. Parasail

9. B#

10.Assembly

• No particular order.

• Based on popularity & following.

Low-Level

vs

High-Level

Programming Languages

Hardware

Machine Language

Assembly Language

High-Level LanguageFortran | C | Pascal

OO & Visual Languages

C++ | D | Rust

Ownership in Rust

Ownership in Rust

• Encapsulates two (02) concepts:

• The lifetime of a value (i.e. when it is valid to interact with it).

• Unique vs Shared Values.

• Leads to a few rules:

• Uniquely-owned values are destroyed when they go out of scope.

• Only uniquely-owned values can be mutated.

• Borrowing a value means it is no longer uniquely owned.

Ownership in Rust (Analogy)

• I have a coloring book, a marker & some friends.

• If I leave, the coloring book & marker leave with me.

• If a friend borrows the book, I can no longer color it.

• My friends can also lend it to other friends.

• If someone leaves while my friends are borrowing the book, they give it back before leaving.

Ownership in Rust (Analogy)

• I can’t leave if the book is still borrowed.

• Either I wait, or I should have given it away.

• I can also lend someone the marker along with the book, if they want to color in it.

How Does Ownership Help?

• Use-After-Free

• Can’t return/store pointer to an object that may be deallocated before pointer.

• Can’t use immutable & mutable pointers to the same object.

• Data Races

• Forced transfer ownership of data or copy when using multiple threads.

• Only types that abide by compiler rules can be shared – ensures type locking/atomic access is used.

Race

Condition

What is Race Condition?• A race condition is…

• An undesirable situation.

• Occurs when a device or system attempts to perform two or more operations at the same time.

• But because of the nature of the device or system, the operations must be done in the proper sequence to be done correctly.

Features of

Rust?

Features of Rust

• Zero-cost abstractions

• Move semantics

• Guaranteed memory safety

• Threads without data races

• Trait-based generics

• Pattern matching

• Type inference

• Minimal runtime

• Efficient C bindings

Projects using Rust

Projects Using Rust

Magic Pocket

Dropbox's file storage system that powers their Diskotech petabyte storage machines.

Servo

Mozilla's new parallel rendering engine developed in collaboration with Samsung.

OpenDNS

Uses Rust in two of its components.

Redox OS

A microkernel operating system being developed in Rust.

Projects Using Rust

Xi Editor

The xi editor project is an attempt to build a high quality text editor, using modern software engineering techniques.

GNU uutils coreutils

uutils is an attempt at writing universal (as in cross-platform) CLI utils in Rust. This repo is to aggregate the GNU coreutils rewrites.

Neon

A safe Rust abstraction layer for native Node.jsmodules.

Installing

Rust

Installing Rust

• Installer for Windows, Mac OS X & Linux available via https://www.rust-lang.org

• If you wish to run Rust on your local machine when you’re offline.

• Rust Playground [https://play.rust-lang.org]

• If you are online, you may opt to use this one instead.

• You may use ANY text editor to code in Rust.

• As a practice, please save your Rust code using .rs file extension.

Rust Playground

Rust Playground (Run)

Function

Main()

Function main()

• Every Rust program must have at least one (01) function.

• Simplest possible function declaration is named as “main”

fn main() {

}

• Functions can also take arguments

fn print_number(x:i32) {

println!(“x is: {}”, x);

}

Hello Worldin Rust

helloworld.rs

fn main()

{

println!(“Hello world in Rust!”);

}

helloworld.rs (Run)

Cargo

Cargo

• A tool that allows Rust projects to declare their various dependencies & ensure that you’ll always get a repeatable build.

• Cargo does:

1. Introduces two (02) metadata files with various bits of project information.

2. Fetches & builds your project’s dependencies.

3. Invokes rustc or another build tool with the correct parameters to build your project.

4. Introduces conventions to make working with Rust projects easier.

Cargo

• To start a new project with Cargo, we invoke in the command line:

cargo new hello_world --bin

• Cargo will generate the following files & folders:

Cargo.toml [file]

src [folder]

main.rs [file]

• Acts as a manifest file

• Contains all of the metadata that Cargo needs to compile your project.

TOML, what?!

TOML

• Tom’s Obvious, Minimal Language (or some say, Tom’s Own Markup Language)

• Created by Tom Preston-Werner

• Aims to be a minimal configuration file format that's easy to read due to obvious semantics.

• Designed to map unambiguously to a hash table.

• Should be easy to parse into data structures in a wide variety of languages.

Cargo.toml

Cargo.toml

[package]

name = "hello_world”

version = "0.1.0”

authors = ["Your Name <you@example.com>"]

IDE Support

IDE Support

• Modern IDEs give developers a massive increase in productivity.

• Several community projects have provided an excellent start towards IDE support.

• Good IDE support requires a number of components:

• The compiler must be modified to operate in a different mode.

• Must provide name & type information from the compiler to the IDE.

• Must write plugins for the IDEs themselves so they know what to do with Rust projects.

IDE Support

• Available IDE Plugins:

• Eclipse [https://github.com/RustDT/RustDT]

• Intellij IDEA [https://github.com/intellij-rust/intellij-rust]

• Visual Studio [https://github.com/PistonDevelopers/VisualRust]

• Editor Plugins:

• Atom [https://atom.io/packages/language-rust]

• Emacs [https://github.com/rust-lang/rust-mode]

• Sublime Text [https://packagecontrol.io/packages/Rust]

• Vim [https://github.com/rust-lang/rust.vim]

• Visual Studio Code [https://github.com/saviorisdead/RustyCode]

More on IDE Support

https://www.rust-lang.org/ides.html

Types & Variables

Variables

• Variable Declaration

fn main() {

let a:u8 = 123;

}

• Whereas

• a variable

• u8 data type (unsigned; 0 or positive; 8-bit)

• 123 value of variable “a”

Numeric Data Types

• i8 8-bit signed integer

• i16 16-bit signed integer

• i32 32-bit signed integer

• i64 64-bit signed integer

• u8 8-bit unsigned integer

• u16 16-bit unsigned integer

• u32 32-bit unsigned integer

• u64 64-bit unsigned integer

• isize pointer-size signed integer

• usize pointer-size unsigned integer

• f32/f64 32/64-bit floating point

Mutability in Rust

Mutability

• The ability to change something.

• Mutable variable binding.

• You’re allowed to change what the binding points to.

let x = 5;

x = 6; will result to an error!

• We can use the mut keyword:

let mut x = 5;

x = 6; no problem; no error!

Constants

• Aside from using variables, we can also declare constants in Rust:

const PI:u8 = 3;

no fixed memory address

memory safety is NOT compromised

static X:i32 = 123;

Operatorsin Rust

Arithmetic Operators

+ addition & array/string concatenation

- subtraction

* multiplication

/ quotient

% remainder

Arithmetic Operators

• Rust DOES NOT support ++ and – used in other programming languages.

• a = a+1; or

• a += 1;

• b = b-1; or

• b -= 1;

• You may also use the following in Rust

• *=

• /=

• %=

Arithmetic Operators

let mut a = 2+3*4;

println!(“Answer = {}.”, a);

let mut a = (2+3)*4;

println!(“Answer = {}.”, a);

Arithmetic Operators

let mut a = 10/3;

println!(“Answer = {}.”, a);

let mut a = 10%3;

println!(“Answer = {}.”, a);

let a=10;

println!(“Remainder of {} / {}

= {}”, a, 3, (a%3));

More Sample

(Try them out)

Arithmetic Operators (eg1)

fn main() {

let num1 = 20;

let num2 = 10;

println!(“The SUM of the numbers =

{}”, (num1 + num2));

println!(”The DIFFERENCE of the

numbers = {}”, (num1 – num2));

… and so on

Arithmetic Operators (eg2)

fn main() {

let num1 = 20;

let num2 = 10;

let sum = num1 + num2;

let dif = num1 – num2;

let pro = num1 * num2;

let quo = num1 / num2;

println!(“The SUM of the numbers =

{}”, sum);

… and so on

Q&A

References

Reference Materials

• The Rust Programming Language Book

• https://doc.rust-lang.org/book/

• Rust by Example

• http://rustbyexample.com

• Rust User Forums

• https://users.rust-lang.org

• https://internals.rust-lang.org

facebook.com/groups/rustph

https://rustph.slack.com

To request an invite:

https://rustphslack.herokuapp.com

Thank you!

Maraming salamat po!

http://www.mozillaphilippines.org

bob@mozillaph.org