tafsiri

#fib with memoization
fakeClosure := Object clone
fakeClosure memo := Map clone
fakeClosure fibmemo := method(num,
  #I need this next line when i assign this method to a slot in the
  #outer object (see last line of this gist).
  #Feels like a 'this/self' binding issue. Otherwise i would have expected 
  #the memo slot on fakeClosure to be visible here
  memo := fakeClosure memo #not strictly necessary when calling 'fakeClosure fibmemo'
  memo atPut(0 asString, 0)

tafsiri

#traditional recursive fib
fib := method(num,
  if(num == 0 or num == 1
    , num
    , fib(num-1) + fib(num-2)
  )
)

tafsiri

#differential inheritance
#making types (objects with a type field)
Shape := Object clone
Shape area := method(width * height)
Shape width := 5
Shape height := 9
Rect := Shape clone
Square := Shape clone
Ellipse := Shape clone

tafsiri

fakeClosure := Object clone do(
  memo := Map clone
  fibmemo := block(num, #note 'blocks' are lexically scoped
    memo atPut(0 asString, 0)
    memo atPut(1 asString, 1)
    fibhelp := method(num,
      one := memo at((num-1) asString)
      two := memo at((num-2) asString)
      if(one == nil
        , one = fibhelp(num-1,memo)

tafsiri

#get rid of the object and just use a method as a container
fibmemoclosure := method(num,
  memo := Map clone
  fibmemo := block(num, #note 'blocks' are lexically scoped
    memo atPut(0 asString, 0)
    memo atPut(1 asString, 1)
    fibhelp := method(num,
      one := memo at((num-1) asString)
      two := memo at((num-2) asString)
      if(one == nil

tafsiri

#Minimal mixins in Io!
Object mix := method(obj,
  #grab all the objects methods and add them to the target
  #the target is the object mixing in the mixin
  mixer := call target
  obj slotNames foreach(slotName,
    if(obj getSlot(slotName) type == "Block"
        , mixer setSlot(slotName, obj getSlot(slotName))
        #ignore properties for the moment
      )

tafsiri

#Actors
#this code is from day 2
Delay := Object clone
Delay send := method(
  args := call message arguments
  for(i,0, args size - 1, 2,
    delay := doMessage(args at(i))
    msg := args at(i+1)

    wait(delay)

tafsiri

#The sleeping barber problem http://en.wikipedia.org/wiki/Sleeping_barber_problem
#Solved with Io actors

Barber := Object clone do(
  sleeping := false
  
  wakeup := method(
    "Waking Up!" println
    sleeping = false
  )

tafsiri

import scala.util.Random

class Game{
  
  val board = Array(Array("_", "_", "_"),
                    Array("_", "_", "_"),
                    Array("_", "_", "_"))

  var currentPlayer = "X"
  

tafsiri

//Experimenting with traits. 
trait Volume {
  //define some methods we need to use to implement the functionality of 
  //this trait, the class using this trait will need to implement these methods
  //concretely.
  def area() : Int
  def height : Int //this can also be a val

  //the functionality provided by this trait
  def volume() = {