teh

import random
import collections

# Generic n-ary tree
RoseTree = collections.namedtuple('RoseTree', 'a children')

def gen_int():
    def _gen_int(rng, size):
        return rng.randrange(0, size)

teh

let
  region = "eu-west-1";

in
{
  resources.ec2KeyPairs.waw-pair = { inherit region; };
  resources.ec2SecurityGroups.http-ssh = {
    inherit region;
    rules = [
        { fromPort = 22; toPort = 22; sourceIp = "0.0.0.0/0"; }

teh

{-# LANGUAGE TemplateHaskell #-}
module ElmDerive where

import Language.Haskell.TH

makeElm :: Name -> Q [Dec]
makeElm t = do
  -- Get list of constructors for type t
  TyConI (DataD _ _ _ constructors _)  <- reify t
  x <- [d| x = "hi" |]

teh

with (import <nixpkgs> {}).pkgs;
let monad-control = pkgs.haskellngPackages.callPackage ./monad-control-0.3.nix {};
    pkg = haskellngPackages.callPackage
            ({ mkDerivation, base, monad-control, stdenv, yesod }:
             mkDerivation {
               pname = "yesod-nix";
               version = "0.1.0.0";
               src = ./.;
               isLibrary = false;
               isExecutable = true;

teh

module Main where

import Python
import Test.QuickCheck
import Test.QuickCheck.Monadic


square :: Int -> IO Int
square = defVV "export = lambda x: x * x"

teh

with (import <nixpkgs> {}).pkgs;

let
  importDeps = stdenv.mkDerivation {
      name = "importDeps";
      src = fetchurl {
         url = "file:///home/tom/testbed/nix-import-stuff/ext.zip";
         sha256 = "0ivhsn2pp1sgzsywnd2x673ff5q62v9715kkw5vyf63rfh7fw9h4";
      };
      phases = "unpackPhase installPhase";

teh

Backwards compatible configuration

If some record can change it's a good idea to use a sum type, e.g. you start out with your new program like this:

data Wibble = WibbleV0 { port :: Int, name :: String }

A year later you have a new feature that requires more info. Now you

teh

def get_records():
    df = pandas.read_json('1.json')
    df = pandas.io.json.json_normalize(df['accidents'])
    for _, row in df.iterrows():
        for c in row['casualties']:
            for i in row['involved']:
                row['caualty_severity'] = c['severity']
                row['caualty_gender'] = c['gender']
                row['caualty_class'] = c['class']
                row['caualty_vehicle'] = c.get('vehicle', 'unknonwn')

teh

{ stdenv, fetchurl, buildPythonPackage, pythonPackages, zeromq3, pyqt4 ? null
, notebookSupport ? true   # ipython notebook
, qtconsoleSupport ? true  # ipython qtconsole
, pylabSupport ? true      # ipython --pylab    (backend: agg - no gui, just file)
, pylabQtSupport ? true    # ipython --pylab=qt (backend: Qt4Agg - plot to window)
}:

# ipython qtconsole works with both pyside and pyqt4. But ipython --pylab=qt
# only works with pyqt4 (at least this is true for ipython 0.13.1). So just use
# pyqt4 for both.

teh

include "globals.mzn";

set of 1..5: a = 1..5; % Nicola, Ed, David, Nick, Nigel
set of 1..5: b = 1..5; % Guinea, Squirrel, Pitbull, Badger, Fish
set of 1..5: c = 1..5; % Moccachino, FlatWhite, Chai, Double Espresso, Decaf
set of 1..5: d = 1..5; % Car, Bike, Train, Plane, Walk
set of 1..5: e = 1..5; % Tartan, Paisly, Gingham, Striped, Polka

array[a] of var a: A;
array[b] of var b: B;