markhibberd

Overview

There are lots of representations for strings. In most languages they pick one set of tradeoffs and run with it. In haskell the "default" implementation (at least the one in the prelude) is a pretty bad choice, but unlike most other languages (really) good implementations exist for pretty much every way you can twist these things. This can be a good thing, but it also leads to confusion, and frustration to find the right types and how to convert them.

Types

NicolasT

type z
type 'a s

(* Sadly enough, without kind restrictions, this still allows nonsense types like *)
type nonsense = int s
(* GHC 7.6 supports this (lifting types to kinds & kind constraints) ;-) *)

type (_, _) llist =
  | Nil : (z, 'a) llist
  | Cons : ('a * ('l, 'a) llist) -> ('l s, 'a) llist

pthariensflame

The Indexed State Monad in Haskell, Scala, and C#

Have you ever had to write code that made a complex series of succesive modifications to a single piece of mutable state? (Almost certainly yes.)

Did you ever wish you could make the compiler tell you if a particular operation on the state was illegal at a given point in the modifications? (If you're a fan of static typing, probably yes.)

If that's the case, the indexed state monad can help!

Motivation

dacr

import scala.collection._
import scala.collection.mutable.{ArrayBuffer,ListBuffer, Builder}
import scala.collection.generic._
import scala.collection.immutable.VectorBuilder



// ================================ CustomTraversable ==================================

object CustomTraversable extends TraversableFactory[CustomTraversable] {  

travitch

{-# LANGUAGE OverloadedStrings, RankNTypes, KindSignatures, FlexibleContexts #-}
module Plugins.NotificationDaemon where

-- xmobar plugin API
import Plugins

import DBus.Bus
import DBus.Client
import DBus.Constants

Philonous

{-# LANGUAGE NoMonomorphismRestriction, ViewPatterns #-}

import XMonad
import System.Exit

import Control.Monad
import Control.Concurrent
import Control.Arrow (second)

mmagm

import Data.List

swap :: Int -> Int -> [a] -> [a]
swap i j xs | i == j    = xs
swap i j xs | otherwise = initial ++ (xs !! b) : middle ++ (xs !! a) : end 
    where [a,b] = sort [i,j]
          initial = take a xs
          middle  = take (b-a-1) (drop (a+1) xs)
          end     = drop (b+1) xs

flashingpumpkin

def coroutine(func):
    """
    A decorator that turns a function with normal input into a coroutine.
    This decorator takes care of priming the coroutine, doing the looping and
    handling the closing.
    
    The first argument of any decorated function is what was received when 
    data was sent to the coroutine via the ``.send`` method. All the other
    ``*args`` and ``**kwargs`` are what was passed to the decorated function
    when instantiating the coroutine.

redinger

Setting up Emacs daemon on OS X

Tired of waiting for emacs to start on OS X? This step by step guide will teach you how to install the latest version of emacs and configure it to start in the background (daemon mode) and use emacsclient as your main editor.

Install Cocoa Emacs

Download the latest pretest version of [Emacs for Mac OS X]: http://emacsformacosx.com/builds

spicycode

# 0 is too far from ` ;)
set -g base-index 1

# Automatically set window title
set-window-option -g automatic-rename on
set-option -g set-titles on

#set -g default-terminal screen-256color
set -g status-keys vi
set -g history-limit 10000