Mediator = require "mediator_lua"
mediator = Mediator() -- instantiate a new mediator

mediator:publish(channel, <data, data, ... >)
mediator:remove(<channel>) 

(channel, callback, <options>, <context>);

function(<data, data ...>, channel);

{
  predicate = function(arg1, arg2) return arg1 == arg2 end
  priority = 0|1|... (array index; max of callback array length, min of 0)
}

{
  id, -- unique identifier
  fn, -- function you passed in
  options, -- options
  context, -- context for fn to be called within
  channel, -- provides a pointer back to its channel
  update(options) -- function that accepts { fn, options, context }
}

Mediator = require("mediator_lua")
local mediator = Mediator()

-- Print data when the "message" channel is published to
-- Subscribe returns a "Subscriber" object
mediator:subscribe({ "message" }, function(data) print(data) end);
mediator:publish({ "message" }, "Hello, world");

  >> Hello, world

-- Print the message when the predicate function returns true
local predicate = function(data) 
  return data.From == "Jack" 
end

mediator.Subscribe({ "channel" }, function(data) print(data.Message) end, { predicate = predicate });
mediator.Publish({ "channel" }, { Message = "Hey!", From = "Jack" })
mediator.Publish({ "channel" }, { Message = "Hey!", From = "Drew" })

  >> Hey!

-- removes all methods bound to a channel 
mediator:remove({ "channel" })

-- unregisters MethodFN, a named function we defined elsewhere, from "channel" 
mediator:remove({ "channel" }, MethodFN)

mediator:publish({ "channel" }, "argument", "another one", { etc: true }); # args go on forever

mediator:subscribe({ "application:chat:receiveMessage" }, function(data){ ... })

-- will recursively call anything in the appllication:chat:receiveMessage namespace 
-- will also call thins directly subscribed to application and application:chat,
-- but not their children
mediator:publish({ "application", "chat", "receiveMessage" }, "Jack Lawson", "Hey")

-- will recursively remove everything under application:chat
mediator:remove({ "application", "chat" })

local sub = mediator:subscribe({ "application", "chat" }, function(data){ ... })
local sub2 = mediator:subscribe({ "application", "chat" }, function(data){ ... })

-- have sub2 executed first
mediator.GetChannel({ "application", "chat" }).SetPriority(sub2.id, 0);

sub:update({ fn: ..., context = { }, options = { ... })

-- for example, let's not post the message if the `from` and `to` are the same
mediator.Subscribe({ "application", "chat" }, function(data, channel) 
  -- throw an error message or something
  channel:stopPropagation()
end, options = {
  predicate = function(data) return data.From == data.To end,
  priority = 0
})