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• Monday, August 6: Chapter 16 hosted by Charlottesville Haskell Book Reading Group in Charlottesville, va, USA
• Monday, August 6: Combinating - The Weekly Function hosted by Orange Combinator - Functional Programming In OC in Irvine, CA
• Tuesday, August 7: Techniques in Functional JavaScript hosted by NoFUN - New Orleans Functional Programming in New Orleans, USA
• Tuesday, August 7: [Lightning talks / Show and tell](https://www.meetup.

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-- Something like this when teaching using GHC
-- so that beginners don't get confused by FTP versions
-- of length, sum, product, etc.
-- Usage: in ghci, `:l FtpFree.hs`

module FtpFree (length, sum, product) where

import  Prelude hiding (length, sum, product)

length :: [a] -> Int

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Using cabal to install quickcheck:

Make a directory to work in.
Inside the directory: “cabal sandbox init”
Then: “cabal install quickcheck”

You can open the GHCI repl in the sandbox:
"cabal repl"

And use normal commands like ":load filename.hs" 

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---Very simple evaluation for arithmetic expressions with only constants 
---(and only "plus"...obviously extendable to other operations)

data Expr = C Float |
            Expr :+ Expr
            deriving Show

eval :: Expr -> Float
eval (C x)         = x
eval (e1 :+ e2)    =  let v1 = eval e1

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module FunkyList where
import Control.Monad

instance Functor FunkyList where
    fmap  = liftM

instance Applicative FunkyList where
    pure  = return
    (<*>) = ap
    

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{-# LANGUAGE FlexibleInstances #-}
module NumFunction where

instance Num a => Num (a -> a) where
 (f + g) x = f x + g x
 (f * g) x = f x * g x
 abs f = abs . f
 signum f = signum . f
 fromInteger x = const (fromInteger x)
 negate f = negate . f

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module Life where

import Data.Set (Set)
import qualified Data.Set as S
import Data.Foldable (foldMap)

type Cell = (Int, Int)

type World = Set Cell

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{-# LANGUAGE ExistentialQuantification #-}

-- This is adapted from http://en.wikibooks.org/wiki/Haskell/Existentially_quantified_types
-- See also https://www.haskell.org/haskellwiki/Heterogenous_collections#Existential_types

module HeterogeneousList where

data ShowBox = forall s. Show s => SB s
 
heteroList :: [ShowBox]

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module Game2048 where

import Graphics.Collage as Collage
import Keyboard
import Random
import Transform2D as TF
import List exposing (..)
import Color exposing (rgb, green, black, grey)
import Graphics.Element exposing (show, color, centered, Element)
import Graphics.Collage exposing (Form)