Simple coroutine manager

--// The coroutine manager | a sample code for DannySMc | by MKlegoman357 \\--

-- this table holds all the coroutines in the format:
-- routines = {
--   {
--     name = name of the coroutine;
--     func = the function of the coroutine;
--     co = the coroutine;
--     filter = the event filter for the coroutine;
--   },
--   ...
-- }

local routines = {}

-- generic function to add a thread, it's not really needed, just here as a 'helper' function
local function addThread (name, func)
  routines[#routines + 1] = {
    name = name;
    func = func;
    co = coroutine.create(func);
    filter = nil;
  }
end

-- this functions simply removes the coroutines by their name
local function removeThread (name)
  local toRemove = {}

  for i, thread in ipairs(routines) do
    if thread.name == name then
      toRemove[#toRemove + 1] = i
    end
  end

  for i = #toRemove, 1, -1 do
    table.remove(routines, toRemove[i])
  end
end

local function run ()
  -- e is a table holding all the event data; event is simply the event string (mouse_down, key, terminate, ...)
  local e, event = {}, nil -- we will have to run the coroutines first, so we'll set the event to be empty

  while #routines > 0 do -- while there are coroutines to run
    -- this table will hold the index of the coroutines which are dead, so we'll be able to remove them later
    local toRemove = {}

    for i, thread in ipairs(routines) do -- for every thread (coroutine, routine - call it whatever)
      -- there are ALWAYS 3 conditions on when to resume a coroutine in ComputerCraft (only one of them has to be true):
      -- 1. the event is 'terminate'
      -- 2. the event filter of the coroutine is nil
      -- 3. the event filter is equal to the coroutine's event filter
      if event == "terminate" or thread.filter == nil or thread.filter == event then
        local ok, filter = coroutine.resume(thread.co, unpack(e)) -- resume the coroutine with the event data

        if not ok then -- if the coroutine errored, print the error
          error(filter, 2)
        end

        -- if the coroutine ended, add it to remove list
        if coroutine.status(thread.co) == "dead" then
          toRemove[#toRemove + 1] = i
        end

        -- don't forget to set the coroutine's filter! It's the same thing that you pass to os.pullEvent( filter )
        thread.filter = filter
      end
    end

    for i = #toRemove, 1, -1 do -- remove all the dead coroutines
      table.remove(routines, toRemove[i])
    end

    -- if there are no more coroutines then break out of the loop. This if is necessary because otherwise the os.pullEventRaw line would be called
    if #routines == 0 then
      break
    end

    -- catch any events and restart the loop to resume the coroutines
    e = {os.pullEventRaw()}
    event = e[1]
  end
end

--[[ Test code ]]--

local function main ()
  print("main")
  sleep(1)
  print("main done")
end

local function bar ()
  print("bar")

  for i = 1, 3 do
    sleep(1)
    print("bar ", i)
  end
end

local function foo ()
  sleep(1)
  print("foo")
  sleep(1)
  addThread("bar", bar)
end

addThread("main", main)
addThread("foo", foo)

print("START")

run()

print("END")