jbpotonnier’s gists

jbpotonnier / numeric_maze.hs

Created October 26, 2012 23:28

Solving http://www.rubyquiz.com/quiz60.html with the power of list monad

	import Control.Monad (guard)

	double :: Int -> Int
	double = (2 *)

	add_two :: Int -> Int
	add_two = (2 +)

	halve :: Int -> Int
	halve n = n `div` 2

jbpotonnier / morse.hs

Created October 16, 2012 21:08

Morse code base in Haskell

	mport Sound.Tomato.Speakers

	sound freq duration = withSpeakers sampleRate 128 $ \s -> playSamples s sound
	where
	sampleRate = 22050
	dt = 1 / sampleRate -- time in seconds of a single sample
	sound = take (ceiling $ duration / dt)
	$ map (0.3*) $ sine freq

	sine freq = [sin (2pifreqdtfromIntegral t) \| t <- [0..]]

jbpotonnier / currency.hs

Created August 13, 2012 20:32

I try to understand phantom types in Haskell. In main, try eur 12 <+> usd 23 and see the compilation error, saying that you cannot add euros and US dollars. Neat ;)

	data EUR
	data USD

	data Amount a = Amount Float deriving Show

	eur :: Float -> Amount EUR
	eur a = Amount a

	usd :: Float -> Amount USD
	usd a = Amount a

jbpotonnier / fizzbuzz.hs

Created August 3, 2012 21:12

My fizz/buzz in Haskell and its direct translation in Python (inspired from http://www.free-variable.org/2009/07/were-not-in-kansas-anymore-toto/ ).

	fizz = cycle ["", "", "fizz"]
	buzz = cycle ["", "", "", "", "buzz"]
	numbers = map show [1..]

	combine "" "" number = number
	combine "fizz" "buzz" _ = "Fizz buzz!"
	combine "fizz" _ _ = "Fizz!"
	combine _ "buzz" _ = "Buzz!"

	fizzbuzz = zipWith3 combine fizz buzz numbers

jbpotonnier / switch_dv_fr

Created July 18, 2012 09:09

Switch between dvorak and fr keyboard. I map it using my window manager

	#!/bin/bash

	kbd=`setxkbmap -query \| grep layout \| awk '{print $2}'`

	if [ 'fr' = $kbd ]
	then
	notify-send 'Keyboard is now Dvorak'
	setxkbmap dvorak en -option compose:ralt
	else
	notify-send 'Keyboard is now French'

jbpotonnier / find_by_key.py

Created June 15, 2012 19:22

Find recursively by key

	def find(d, key):
	if key in d:
	yield d[key]
	for c in d.get('children', []):
	for e in find(c, key): yield e

jbpotonnier / grep_gist.rb

Created June 14, 2012 23:14

Grep in gist description and display url

	require 'net/http'
	require 'uri'
	require 'json'

	def github(*list)
	URI('https://api.github.com/' + list.join('/'))
	end

	def get(uri)
	request = Net::HTTP::Get.new uri.request_uri

jbpotonnier / .gitignore

Created June 5, 2012 21:10

Paths in ul-li

	bin
	local
	include
	lib
	man
	.Python
	*.pyc
	*.swp

jbpotonnier / model.py

Created June 4, 2012 21:50

Very basic json validation (you more likely want something like kwalify or WTForm)

	from exceptions import Exception

	def is_valid(model, instance):
	missing_fields = set(model) - set(instance)
	if missing_fields:
	raise MissingFields(missing_fields)
	missing_types = set(instance) - set(model)
	if missing_types:
	raise MissingTypes(missing_types)
	type_errors = [(k, model[k], type(v)) for (k, v) in instance.items() if type(v) is not model[k]]

jbpotonnier / map.hs

Created June 4, 2012 21:46

map is just fold, or is it the other way around :P Is fold enough to have map, filter, and recursion?


	foldlmap :: (a -> b) -> [a] -> [b]
	foldlmap f = foldl (\ a b -> a ++ [f b]) []


	foldrmap :: (a -> b) -> [a] -> [b]
	foldrmap f = foldr (\ a b -> (f a) : b) []

	main :: IO ()
	main = do

Jean-Baptiste Potonnier jbpotonnier