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var connections = Bacon.fromBinder(function(sink) {
  io.on('connection', sink)
});

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var request = require('request-json'),
    express = require('express'),
    app     = express(),
    http    = require('http').Server(app),
    io      = require('socket.io'),
    db      = require('mongodb').MongoClient;

///////////////////////////////////////////////////////////
// boilerplate code: ignore
//

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var request = require('request-json'),
    express = require('express'),
    app     = express(),
    http    = require('http').Server(app),
    io      = require('socket.io'),
    Bacon   = require('baconjs').Bacon,
    client  = request.newClient('http://localhost:3000/api/'),
    db      = require('mongodb').MongoClient;

///////////////////////////////////////////////////////////

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Bacon.js + Node.js: Functional Reactive Programming on the Server

What

The following demonstrates the usage of the Bacon.js library in implementing a Node.js chat application in the functional reactive programming style. We'll start by re-implementing the canonical Socket.IO chat application in an FRP-idiomatic way, moving on to stream composition, sampling, debouncing, error handling and logging.

Why

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/*

We'll be building a chat application for Seattle-based weather aficionados. 
On top of basic chat functionality (sending messages to a chat room, being 
notified when users enter/leave the room), the application will provide two 
interesting, user-facing features:

1. New users, upon connection to the server, will be sent a private message 
containing a summary of the current weather in Seattle.

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class Prunable
  THIRTY_DAYS_AGO_SEC = 60 * 60 * 24 * 30

  def self.from_assets(exclusion_time, assets)
    assets.select do |asset|
      self.is_prunable?(exclusion_time, asset)
    end
  end

  def self.is_prunable?(exclusion_time, asset)

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module Main where

import Control.Applicative

-- represents our API - its constructor takes two functions
--
data API = API { apiDouble :: Integer -> Integer, apiTriple :: Integer -> Integer }

-- run a pure function as a computation in the IO monad.
-- note that the function won't be run until you bind the

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CHALLENGE #3

HIGHER-ORDER FUNCTIONS

1. implement a function "foldFromRight" which takes:

• a function with two parameters (a "binary function")
• a starting value (the accumulator)
• a list of values to reduce into a single value

The behavior of your foldFromRight function will be similar to "reduce" in JavaScript and Ruby - except for the fact that it will move from the end of the list to the beginning (instead of from the beginning to the end).

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module Main where

-- essentially we're defining functions that makes sense to
-- call with things that can be doubled. it can be, well,
-- a value of any type (as long as that type instantiates
-- the Dubbleable type class). Dispatch can happen by virtue
-- of what you're going to do with the return value of the
-- function or what you're passing to the function as its
-- arguments
--

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struct MatchSearch {
  combineId             int [optional]
}

struct Match {
  id                    int
  name                  string
  startsAt              int
  teams                 []Team
  heats                 []Heat