Paul Callaghan paulcc

paulcc / gist:5abb741d6eef893886c9

Created November 27, 2015 14:32 — forked from steshaw/gist:8142387

Paul Callaghan's FP/DT articles

paulcc / gist:5870420

Last active December 19, 2015 00:39

Bits of the word pack code in Idris

	placeholder... until a few more days into July

paulcc / wpc_10.hs

Last active December 17, 2015 18:59

	-- using Haskell's library for rational numbers, which stores a rational as
	-- a pair of integer numbers (not limited to 32 or 64 bits); hence able to do
	-- exact arithmetic etc up to high numbers
	import Data.Ratio

	-- the core function: spits out a list of ascending n for the fractions
	-- works by reducing (a/b) to 1/ceil(b/a) + ...
	fractionize t
	\| t == 0 = []
	\| diff >= 0 = next : fractionize diff

paulcc / wpc_four.hs

Created April 15, 2013 10:28

	import Data.List(nub, sortBy, groupBy)
	import Data.Char(isAlpha, toLower)

	isograms s
	= [ (length w, w)
	\| w <- nub $ words $ map toLower s
	, all isAlpha w
	, nub w == w ]

	main = do text <- readFile "pg11.txt"

paulcc / gist:4577526

Last active December 11, 2015 09:08

Placeholder

paulcc / gist:4477087

Last active December 10, 2015 18:48 — forked from anonymous/gist:4477082

Haskell version of code from http://blog.8thlight.com/uncle-bob/2013/01/07/FPBE3-Do-the-rules-change.html

	-- see below for commentary

	makeUpTo :: Int -> [String] -> [String]
	makeUpTo n = mlu []
	where
	mlu pre [] = [pre]
	mlu [] (w:ws) = mlu w ws
	mlu pre (w:ws) \| length pre + 1 + length w <= n = mlu (pre ++ ' ' : w) ws
	\| otherwise = pre : mlu [] (w:ws)

paulcc / Files.hs

Created November 27, 2012 23:02

Async JS via Fay (Haskell) - see the December PragPub Magazine article

	{-# LANGUAGE RankNTypes #-}
	{-# LANGUAGE NoImplicitPrelude #-}
	{-# LANGUAGE NoMonomorphismRestriction #-}

	-- Example for December 2012 Prag Pub Magazine
	-- expects Fay 0.10
	--
	-- Fay doesn't support type classes yet (hopefully soon) so this code contains
	-- various workarounds and so is a bit more complex than it should be!

paulcc / gist:3799331

Created September 28, 2012 11:43

list of four-letter words to go with https://gist.github.com/3733182

paulcc / gist:3733182

Created September 16, 2012 16:51

Code for the Word Chain kata, see the October edition of PragPub magazine

	-- word list is at https://gist.github.com/3799331

	import Data.Set(Set, fromDistinctAscList, member)
	import System.IO.Unsafe(unsafePerformIO)

	import Data.Tree
	import Data.List(inits,tails)

	--------------------
	-- first step - generating valid next words

paulcc / group_on-full-example.hs

Created September 5, 2012 17:37

Example to accompany my types in haskell article

	-- compiles with ghc(i) 7.4.1
	import Data.Map (Map, empty, insertWith, toList)
	import Data.List(groupBy, group, sortBy, sort)

	{- To recap from the main article, we want to define "group_on" via "groupBy", so that its
	type is something like (b -> b -> Bool) -> (a -> b) -> [a] -> [(b, [a])]

	The method here is to work with a concrete example and gradually massage it
	into the form we want - using the REPL