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A series of reading lists mostly related to functional programming.

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data Todo = Todo {
  id :: Text,
  created :: UTCTime,
  title :: Text,
  description :: Text,
  priority :: Int
}

data Command
  = Add Main.Todo

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Laws that apply to our industry (and others) are interesting to me, and I'm writing up here the ones that often come to mind. I usually forget the name, so writing them up might be helpful for remembering in future.

Parkinson's law

C. Northcote Parkinson's law: Work expands so as to fill the time available for its completion. Similarly, in computing, data expands to fill the space available for storage,

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#!/usr/bin/env hell

-- How to run this:
--
-- socat TCP-LISTEN:8081,fork,reuseaddr,max-children=20 EXEC:"./handler.hell"

main = do
 line <- Text.getLine
 let content =
      Text.concat ["<h1>Hello, World!</h1><p>This is generated by Hell.</p><pre>", line, "</pre>"]

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{-

Examples:

> reify @Int $ eval $ A (reflect (abs :: Int -> Int)) (I (-9))
9

> reify @Int $ eval $ A (A (reflect ((*) :: Int -> Int -> Int)) (reflect @Int 3)) (reflect @Int 5)
15

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-- Credit to: https://news.ycombinator.com/item?id=15186988

let iterate
    : (Natural → Natural) → Natural → Natural
    =   \f n ->
          fold (n + 1) f 1

let increment : Natural → Natural = \n -> n + 1

let ackermann

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extern crate time;

use std::fs::File;
use std::io::prelude::*;

fn main() {
    let mut inpt = File::open("input/xmas5.txt").expect("file not found");
    let mut content = String::new();
    inpt.read_to_string(&mut content).unwrap();
    let tm = time::now();

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{-# LANGUAGE NamedFieldPuns #-}

-- The Expression Problem and my sources:
-- http://stackoverflow.com/questions/3596366/what-is-the-expression-problem
-- http://blog.ontoillogical.com/blog/2014/10/18/solving-the-expression-problem-in-clojure/
-- http://eli.thegreenplace.net/2016/the-expression-problem-and-its-solutions/
-- http://www.ibm.com/developerworks/library/j-clojure-protocols/


-- To begin demonstrating the problem, we first need some

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{-# LANGUAGE OverloadedLabels, TypeOperators, DataKinds, FlexibleContexts #-}
{-# LANGUAGE OverloadedStrings #-}
import Labels
import Labels.Cassava
import Data.Vector ( Vector )
import Data.Text ( Text )
import Data.Text.Lazy.Encoding
import qualified Data.Text.Lazy as LT
import Data.Csv hiding ( decodeByName )
import Data.Csv.Streaming

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