Learn You Some Erlang

Explore the world of Erlang programming through this comprehensive tutorial covering everything from basic syntax to advanced concepts like concurrency, OTP applications, and distributed systems. Learn about functional programming, pattern matching, recursion, error handling, and building robust applications. Dive into topics such as supervision trees, release management, testing with EUnit and Common Test, working with Mnesia database, and understanding type specifications. Gain practical experience by implementing various projects and examples throughout the tutorial, preparing you for real-world Erlang development.

Introduction

• About this tutorial
• So what's Erlang?
• Don't drink too much Kool-Aid
• What you need to dive in
• Where to get help

Starting Out

• The Shell
• Shell Commands

Starting Out (for real)

• Numbers
• Invariable Variables
• Atoms
• Boolean Algebra and Comparison Operators
• Tuples
• Lists
• List Comprehensions
• Bit Syntax
• Binary Comprehensions

Modules

• What are modules
• Module Declaration
• Compiling the Code
• More About Modules

Syntax in Functions

• Pattern Matching
• Guards, Guards!
• What the If!?
• In Case ... of
• Which to use?

Types (or lack thereof)

• Dynamite-strong Typing
• Type Conversions
• To Guard a Data Type
• For Type Junkies

Recursion

• Hello recursion!
• Length
• Length of Tail Recursion
• More recursive functions
• Quick, Sort!
• More than lists
• Thinking recursively

Higher Order Functions

• Let's get functional
• Anonymous functions
• Maps, filters, folds and more

Errors and Exceptions

• Not so fast!
• A Compilation of Errors
• No, YOUR logic is wrong!
• Run-time Errors
• Raising Exceptions
• Dealing with Exceptions
• Wait, there's more!
• Try a try in a tree

Functionally Solving Problems

• Reverse Polish Notation Calculator
• Heathrow to London

A Short Visit to Common Data Structures

• Won't be too long, promised!
• Records
• Key-Value Stores
• Arrays
• A Set of Sets
• Directed Graphs
• Queues
• End of the short visit

The Hitchhiker's Guide to Concurrency

• Don't Panic
• Concepts of Concurrency
• Not Entirely Unlike Linear Scaling
• So long and thanks for all the fish!

More On Multiprocessing

• State Your State
• We love messages, but we keep them secret
• Time Out
• Selective Receives

Errors and Processes

• Links
• It's a Trap!
• Monitors
• Naming Processes

Designing a Concurrent Application

• Understanding the Problem
• Defining the Protocol
• Lay Them Foundations
• An Event Module
• The Event Server
• Hot Code Loving
• I Said, Hide Your Messages
• A Test Drive
• Adding Supervision
• Namespaces (or lack thereof)

What is OTP?

• It's The Open Telecom Platform!
• The Common Process, Abstracted
• The Basic Server
• Specific Vs. Generic

Clients and Servers

• Callback to the Future
• .BEAM me up, Scotty!

Rage Against The Finite-State Machines

• What Are They?
• Generic Finite-State Machines
• A Trading System Specification
• Game trading between two players
• That Was Quite Something
• Fit for the Real World?

Event Handlers

• Handle This! *pumps shotgun*
• Generic Event Handlers
• It's Curling Time!
• Alert The Press!

Who Supervises The Supervisors?

• From Bad to Good
• Supervisor Concepts
• Using Supervisors
• Child Specifications
• Testing it Out
• Dynamic Supervision

Building an Application With OTP

• A Pool of Processes
• The Onion Layer Theory
• A Pool's Tree
• Implementing the Supervisors
• Working on the Workers
• Writing a Worker
• Run Pool Run
• Cleaning the Pool

Building OTP Applications

• Why Would I Want That?
• My Other Car is a Pool
• The Application Resource File
• The Application Behaviour
• From Chaos to Application
• Library Applications

The Count of Applications

• From OTP Application to Real Application
• Run App Run
• Included Applications
• Complex Terminations

Release is the Word

• Am I an Executable Yet?
• Fixing The Leaky Pipes
• Releases With Systools
• Releases With Reltool
• Recipes
• Released From Releases

Leveling Up in The Process Quest

• The Hiccups of Appups and Relups
• The 9th Circle of Erl
• Progress Quest
• Making Process Quest Better
• Appup Files
• Upgrading the Release

Buckets Of Sockets

• IO Lists
• TCP and UDP: Bro-tocols
• UDP Sockets
• TCP Sockets
• More Control With Inet
• Sockserv, Revisited
• Where to go From Now?

EUnited Nations Council

• The Need for Tests
• EUnit, What's a EUnit?
• Test Generators
• Fixtures
• Testing Regis
• He Who Knits Eunits

Bears, ETS, Beets

• The Concepts of ETS
• ETS Phone Home
• Meeting Your Match
• You Have Been Selected
• DETS
• A Little Less Conversation, A Little More Action Please

Distribunomicon

• Alone in the Dark
• This is my Boomstick
• Fallacies of Distributed Computing
• Dead or Dead Alive
• My Other CAP is a Theorem
• Setting up an Erlang Cluster
• Cookies
• Remote Shells
• Hidden Nodes
• The Walls are Made of Fire and the Goggles do Nothing
• The Calls from Beyond
• Burying the Distribunomicon

Distributed OTP Applications

• Adding More to OTP
• Taking and Failing Over
• The Magic 8-Ball
• Making the Application Distributed

Common Test for Uncommon Tests

• What is Common Test
• Common Test Cases
• Testing With State
• Test Groups
• The Meeting Room
• Test Suites
• Test Specifications
• Large Scale Testing
• Integrating EUnit within Common Test
• Is There More?

Mnesia And The Art of Remembering

• What's Mnesia
• What Should the Store Store
• From Record to Table
• Of Schemas and Mnesia
• Creating Tables for Real
• Access and Context
• Reads, Writes, and More
• Implementing The First Requests
• Accounts And New Needs
• Meet The Boss
• Deleting Stuff, Demonstrated
• Query List Comprehensions
• Remember Mnesia

Type Specifications and Erlang

• PLT Are The Best Sandwiches
• Success Typing
• Type Inference and Discrepancies
• Typing About Types of Types
• Typing Functions
• Typing Practice
• Exporting Types
• Typed Behaviours
• Polymorphic Types
• You're my Type

Conclusion

• A Few Words
• Other Topics
• LYSE as a book

Postscript: Maps

• About This Chapter
• EEP, EEP!
• What Maps Shall Be
• Stubby Legs for Early Releases
• Mexican Standoff
• How This Book Would Be Revised For Maps

Postscript: Time Goes On

• On Time for Time
• How Things Were
• How Things Are (18.0+)
• Time Warp
• How to Survive Time Warps