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* Preface

Welcome to 8sync's documentation!
8sync is an asynchronous programming environment for GNU Guile.
(Get it? 8sync? Async??? Quiet your groans, it's a great name!)

8sync has some nice properties:

 - 8sync uses the actor model as its fundamental concurrency
   synchronization mechanism.
   Since the actor model is a "shared nothing" asynchronous
   environment, you don't need to worry about deadlocks or other
   tricky problems common to other asynchronous models.
   Actors are modular units of code and state which communicate
   by sending messages to each other.
 - If you've done enough asynchronous programming, you're probably
   familiar with the dreaded term "callback hell".
   Getting around callback hell usually involves a tradeoff of other,
   still rather difficult to wrap your brain around programming
   patterns.
   8sync uses some clever tricks involving "delimited continuations"
   under the hood to make the code you write look familiar and
   straightforward.
   When you need to send a request to another actor and get some
   information back from it without blocking, there's no need
   to write a separate procedure... 8sync's scheduler will suspend
   your procedure and wake it back up when a response is ready.
 - Even nonblocking I/O code is straightforward to write.
   Thanks to the "suspendable ports" code introduced in Guile 2.2,
   writing asynchronous, nonblocking networked code looks mostly
   like writing the same synchronous code.
   8sync's scheduler handles suspending and resuming networked
   code that would otherwise block.
 - 8sync aims to be "batteries included".
   Useful subsystems for IRC bots, HTTP servers, and so on are
   included out of the box.
 - 8sync prioritizes live hacking.
   If using an editor like Emacs with a nice mode like Geiser,
   an 8sync-using developer can change and fine-tune the behavior
   of code /while it runs/.
   This makes both debugging and development much more natural,
   allowing the right designs to evolve under your fingertips.
   A productive hacker is a happy hacker, after all!

In the future, 8sync will also provide the ability to spawn and
communicate with actors on different threads, processes, and machines,
with most code running the same as if actors were running in the same
execution environment.

But as a caution, 8sync is still very young.
The API is stabilizing, but not yet stable, and it is not yet well
"battle-tested".
Hacker beware!
But, consider this as much an opportunity as a warning.
8sync is in a state where there is much room for feedback and
contributions.
Your help wanted!

And now, into the wild, beautiful frontier.
Onward!

* Tutorial

** Intro to the tutorial

IRC!  Internet Relay Chat!
The classic chat protocol of the Internet.
And it turns out, one of the best places to learn about networked
programming.

In the 1990s I remember stumbling into some funky IRC chat rooms and
being astounded that people there had what they called "bots" hanging
around.
From then until now, I've always enjoyed encountering bots whose range
of functionality has spanned from saying absurd things, to taking
messages when their "owners" were offline, to reporting the weather,
to logging meetings for participants.
And it turns out, IRC bots are a great way to cut your teeth on
networked programming; since IRC is a fairly simple line-delineated
protocol, it's a great way to learn to interact with sockets.
(My first IRC bot helped my team pick a place to go to lunch, previously
a source of significant dispute!)
At the time of writing, venture capital awash startups are trying to
turn chatbots into "big business"... a strange (and perhaps absurd)
thing given chat bots being a fairly mundane novelty amongst hackers
and teenagers everywhere in the 1990s.

We ourselves are going to explore chat bots as a basis for getting our
feet wet in 8sync.
We'll start from a minimalist example using an irc bot with most of
the work done for us, then move on to constructing our own actors as
"game pieces" which interface with our bot, then experiment with just
how easy it is to add new networked layers by tacking on a high score
to our game, and as a finale we'll dive into writing our own little
irc bot framework "from scratch" on top of the 8sync actor model.

Alright, let's get going.
This should be a lot of fun!

** A silly little IRC bot

** Battle bot!

** Adding a "rankings" web page

** Writing our own <irc-bot> from scratch

* API reference