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[
    {
        "city": "New York", 
        "growth_from_2000_to_2013": "4.8%", 
        "latitude": 40.7127837, 
        "longitude": -74.0059413, 
        "population": "8405837", 
        "rank": "1", 
        "state": "New York"
    }, 

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{-# LANGUAGE DataKinds, PolyKinds, TypeOperators #-}
{-# LANGUAGE TypeFamilies, FlexibleInstances, ScopedTypeVariables #-}
{-# LANGUAGE InstanceSigs #-}

module TinyServant where

import Control.Applicative
import GHC.TypeLits
import Text.Read
import Data.Time

seagreen

Installation of NixOS with encrypted root

These are my notes on instaling NixOS 16.03 on a Lenovo ThinkPad X1 Carbon (4th generation) with an encrypted root file system using UEFI.

Most of this is scrambled from the following pages:

• Encrypted Root on NixOS - Nix Wiki
• Installing NixOS - Chris Martin
• Linux administration and use - Earl Douglas
• Installing NixOS on a ThinkPad W540 with encrypted root - Bluish Coder

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At work, I just spent the last few weeks exploring and evaluating every format I could find, and my number one criteria was whether they supported sum types. I was especially interested in schema languages in which I could describe my types and then some standard specifies how to encode them using an on-the-wire format, usually JSON.

1. Swagger represents sum types like Scala does, using subtyping. So you have a parent type EitherIntString with two subtypes Left and Right represented as {"discriminator": "Left", value: 42} and {"discriminator": "Right", value": "foo"}. Unfortunately, unlike in Scala in which the parent type is abstract and cannot be instantiated, in Swagger it looks like the parent type is concrete, so when you specify that your input is an EitherIntString, you might receive {"discriminator": "EitherIntString"} instead of one of its two subtypes.
2. JSON-schema supports unions, which isn't quite the same thing as sum types because