benkolera

  crank-docker = nixpkgs.dockerTools.buildImage {
    name = "crank-docker";
    fromImage = nixpkgs.dockerTools.pullImage {
      imageName = "alpine";
      imageTag = "3.6";
      sha256 = "1sd6p2k3d1dw6apkcj25m5kpkih83jiikgvbzxsqnlfy2y9gyphr";
    };
    contents = [
      crank
      nixpkgs.pkgs.cacert

benkolera

{ nixpkgs  ? <nixpkgs> }:

import ./package.nix {
  inherit (nixpkgs) stdenv fetchurl makeWrapper jre;
}

benkolera

# Terminal 1
sos 'hello.hs' -c 'ghcjs hello.hs'

# Terminal 2 in ./hello.jsexe/
node -e <EOF
var connect  = require('connect');
var static = require('serve-static');

var server = connect();

benkolera

Thinking with Types - Ben Kolera

A core restriction of functional programming is that functions can only use their inputs to calculate their output and thus must always return the same output for a given input. This has the lovely effect that we can reason about what a function does purely by the the types of their inputs and outputs and use that knowledge when refactoring and composing functional programs.

The types are our key to reducing the possibilities of inputs and outputs of our functions. As we reduce the possibilities and weaken what our function can

benkolera

# Made with Sonic Pi v2.8
# http://sonic-pi.net

live_loop :bass do
  4.times do
    sample :bass_hard_c, amp: 2;
    sleep 1
    2.times do
      sample :bass_hit_c, amp: 4;
      sleep 0.5

benkolera

# Sonic Pi track
# http://sonic-pi.net

our_chord = chord(:a5)
base      = :a5

live_loop :melody do
  with_fx :slicer do
    35.times do
      play our_chord.choose, attack: 0, release: 0.3, pan: rrand(-1,1), amp: 0.4

benkolera

class PGHasTimestamp a where
instance PGHasTimestamp PGDate
instance PGHasTimestamp PGTimestamp
instance PGHasTimestamp PGTimestamptz

class PGHasDate a where
instance PGHasDate PGDate
instance PGHasDate PGTimestamp
instance PGHasDate PGTimestamptz

benkolera

data Pagination = Pagination
  { _paginationPage  :: Int
  , _paginationWidth :: Int
  }
makeLenses ''Pagination

data PaginationResults a = PaginationResults
  { _paginationResultsPage    :: Int
  , _paginationResultsWidth   :: Int
  , _paginationResultsMaxPage :: Int64

benkolera

{-# LANGUAGE OverloadedStrings #-}
module Main where

import Data.List.NonEmpty (NonEmpty((:|)))
import qualified Data.List.NonEmpty as NEL
import Data.Monoid ((<>))
import qualified Data.Text as T
import Data.Text (Text)

chars :: NonEmpty Char

benkolera

ben at Bens-MacBook-Pro in ~
$ cat ~/.nixpkgs/haskell/ghc-mod.nix
{ mkDerivation, async, base, bytestring, cabal-helper, cereal
, containers, data-default, deepseq, directory, djinn-ghc, doctest
, emacs, fetchgit, filepath, ghc, ghc-paths, ghc-syb-utils
, haskell-src-exts, hlint, hspec, makeWrapper, monad-control
, monad-journal, mtl, old-time, pretty, process, split, stdenv, syb
, temporary, text, time, transformers, transformers-base
}:
mkDerivation {