Ian Jeffries 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:

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.

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.
JSON-schema supports unions, which isn't quite the same thing as sum types because

Intro

The JSON Schema spec doesn't speak on error construction at all (which is absolutely the right decision).

This means that each library author has to figure out how to construct informative errors individually.

This document is meant to sketch out some best practices.

Example

slides

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

	src/EasyTest.hs:213:1: error: bool is unused

	211 ┃
	212 ┃ bool :: Test Bool
	213 ┃ bool = random
	214 ┃
	215 ┃ word8 :: Test Word8

	Delete this definition or add ‘EasyTest.bool’ as a root to fix this error.

	{-# LANGUAGE ScopedTypeVariables #-}

	-- Based off of: https://github.com/ajnsit/concur/issues/17#issuecomment-516804859
	module Lib where

	import Control.Applicative
	import Concur.Core
	import Concur.Replica (HTML)
	import Control.Concurrent.STM
	import Prelude

	{-# 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

	#
	# There is insufficient memory for the Java Runtime Environment to continue.
	# Native memory allocation (malloc) failed to allocate 32744 bytes for ChunkPool::allocate
	# Possible reasons:
	# The system is out of physical RAM or swap space
	# In 32 bit mode, the process size limit was hit
	# Possible solutions:
	# Reduce memory load on the system
	# Increase physical memory or swap space
	# Check if swap backing store is full

	Version 1.1.2 x86_64 hpack-0.14.1
	2016-08-06 21:11:59.162271: [debug] Checking for project config at: /home/traveller/code/mine/tf-random/stack.yaml @(stack-1.1.2-DgLojysm1GF2dDrMpykv6D:Stack.Config src/Stack/Config.hs:811:9)
	2016-08-06 21:11:59.163222: [debug] Loading project config file stack.yaml @(stack-1.1.2-DgLojysm1GF2dDrMpykv6D:Stack.Config src/Stack/Config.hs:829:13)
	2016-08-06 21:11:59.166053: [debug] Using a nix-shell environment from file: /home/traveller/code/mine/tf-random/shell.nix @(stack-1.1.2-DgLojysm1GF2dDrMpykv6D:Stack.Nix src/Stack/Nix.hs:111:6)
	2016-08-06 21:11:59.166215: [debug] Run process: nix-shell --pure /home/traveller/code/mine/tf-random/shell.nix --run "'/nix/store/i4nrh5f31a67ijpn9vf587lrlssg5mgq-stack-1.1.2/bin/stack' $STACK_IN_NIX_EXTRA_ARGS '--internal-re-exec-version=1.1.2' 'haddock' '--verbose'" @(stack-1.1.2-DgLojysm1GF2dDrMpykv6D:Stack.Exec src/Stack/Exec.hs:64:5)
	Version 1.1.2 x86_64 hpack-0.14.1
	2016-08-06 21:12:00.438458: [debug] Checking for project config at: /home/t