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@ctford
ctford / lenses.clj
Created July 12, 2014 20:40
A Clojure lens implementation based on focus and fmap.
(ns shades.lenses)
; We only need three fns that know the structure of a lens.
(defn lens [focus fmap] {:focus focus :fmap fmap})
(defn view [x {:keys [focus]}] (focus x))
(defn update [x {:keys [fmap]} f] (fmap f x))
; The identity lens.
(defn fapply [f x] (f x))
(def id (lens identity fapply))
@staltz
staltz / introrx.md
Last active May 7, 2024 09:38
The introduction to Reactive Programming you've been missing
source :rubygems
# We are not loading Active Record, nor Active Resources etc.
# We can do this in any app by simply replacing the rails gem
# by the parts we want to use.
gem "actionpack", "~> 4.0"
gem "railties", "~> 4.0"
gem "tzinfo"
# Let's use thin

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns                     on recent CPU
L2 cache reference ........................... 7 ns                     14x L1 cache
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns                     20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs 4X memory

@jbenet
jbenet / simple-git-branching-model.md
Last active April 9, 2024 03:31
a simple git branching model

a simple git branching model (written in 2013)

This is a very simple git workflow. It (and variants) is in use by many people. I settled on it after using it very effectively at Athena. GitHub does something similar; Zach Holman mentioned it in this talk.

Update: Woah, thanks for all the attention. Didn't expect this simple rant to get popular.

@tonyg
tonyg / mtl2.rkt
Last active December 18, 2015 22:59
From zero to cooperative threads in 15 lines of Racket code (after <http://www.haskellforall.com/2013/06/from-zero-to-cooperative-threads-in-33.html>)
#lang racket/base
(require data/queue)
(provide fork yield done run-threads)
(define current-runqueue (make-parameter #f))
(define (fork thunk)
(enqueue! (current-runqueue) (lambda () (thunk) (done))))
(define (yield)
@lpereira
lpereira / partial.c
Last active January 29, 2023 20:12
Partial functions in C This program illustrates a hack to create partial functions in C. The way it works is that it generates a template function (partial_template_function) with known pointers, that is later copied to a region of memory obtained with mmap(), patched up with the address and data to be passed to the real function, and then made …
/*
* Partial applied functions in C
* Leandro Pereira <leandro@tia.mat.br>
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <stdbool.h>
@jakeonrails
jakeonrails / Ruby Notepad Bookmarklet
Created January 29, 2013 18:08
This bookmarklet gives you a code editor in your browser with a single click.
data:text/html, <style type="text/css">#e{position:absolute;top:0;right:0;bottom:0;left:0;}</style><div id="e"></div><script src="http://d1n0x3qji82z53.cloudfront.net/src-min-noconflict/ace.js" type="text/javascript" charset="utf-8"></script><script>var e=ace.edit("e");e.setTheme("ace/theme/monokai");e.getSession().setMode("ace/mode/ruby");</script>
@andkerosine
andkerosine / raskell.rb
Created August 15, 2012 05:56
Haskell-like list comprehensions in Ruby
$stack, $draws = [], {}
def method_missing *args
return if args[0][/^to_/]
$stack << args.map { |a| a or $stack.pop }
$draws[$stack.pop(2)[0][0]] = args[1] if args[0] == :<
end
class Array
def +@
@brandonb927
brandonb927 / osx-for-hackers.sh
Last active May 5, 2024 13:30
OSX for Hackers: Yosemite/El Capitan Edition. This script tries not to be *too* opinionated and any major changes to your system require a prompt. You've been warned.
#!/bin/sh
###
# SOME COMMANDS WILL NOT WORK ON macOS (Sierra or newer)
# For Sierra or newer, see https://github.com/mathiasbynens/dotfiles/blob/master/.macos
###
# Alot of these configs have been taken from the various places
# on the web, most from here
# https://github.com/mathiasbynens/dotfiles/blob/5b3c8418ed42d93af2e647dc9d122f25cc034871/.osx