chocolateboy

I've even seen implementations that compare objects using JSON.stringify.

I would expect a memoizer and most hash code/table implementations to treat { foo: "bar", baz: "quux" } and { baz: "quux", foo: "bar" } as equivalent, but many implementations use JSON.stringify, which doesn't guarantee this:

$ node
> JSON.stringify({ foo: "bar", baz: "quux" })
'{"foo":"bar","baz":"quux"}'
> JSON.stringify({ baz: "quux", foo: "bar" })
'{"baz":"quux","foo":"bar"}'

otobrglez

# Simple Recommendation Engine in Ruby
# Visit: http://otobrglez.opalab.com
# Author: Oto Brglez <otobrglez@gmail.com>

class Book < Struct.new(:title)

  def words
    @words ||= self.title.gsub(/[a-zA-Z]{3,}/).map(&:downcase).uniq.sort
  end

mangecoeur

Easy parallel python with concurrent.futures

As of version 3.3, python includes the very promising concurrent.futures module, with elegant context managers for running tasks concurrently. Thanks to the simple and consistent interface you can use both threads and processes with minimal effort.

For most CPU bound tasks - anything that is heavy number crunching - you want your program to use all the CPUs in your PC. The simplest way to get a CPU bound task to run in parallel is to use the ProcessPoolExecutor, which will create enough sub-processes to keep all your CPUs busy.

We use the context manager thusly:

with concurrent.futures.ProcessPoolExecutor() as executor:

Nagyman

Workflows (States) in Django

I'm going to cover a simple, but effective, utility for managing state and transitions (aka workflow). We often need to store the state (status) of a model and it should only be in one state at a time.

Common Software Uses

• Publishing (Draft->Approved->Published->Expired->Deleted)

lelandbatey

Description

This simple script will take a picture of a whiteboard and use parts of the ImageMagick library with sane defaults to clean it up tremendously.

The script is here:

#!/bin/bash
convert "$1" -morphology Convolve DoG:15,100,0 -negate -normalize -blur 0x1 -channel RBG -level 60%,91%,0.1 "$2"

Results

fdstevex

+ (NSDictionary *)downloadableFonts
{
    CTFontDescriptorRef desc = CTFontDescriptorCreateWithAttributes((CFDictionaryRef)@{(id)kCTFontDownloadableAttribute : (id)kCFBooleanTrue});
  CFArrayRef matchedDescs = CTFontDescriptorCreateMatchingFontDescriptors(desc, NULL);
    NSArray *array = (__bridge NSArray *)matchedDescs;
    
    NSMutableDictionary *families = [NSMutableDictionary dictionary];

    for (UIFontDescriptor *fontDescriptor in array) {
        NSString *familyName = fontDescriptor.fontAttributes[UIFontDescriptorFamilyAttribute];

jbenet

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.

shadabahmed

#! /bin/sh
### BEGIN INIT INFO
# Provides:          logstash
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Start daemon at boot time
# Description:       Enable service provided by daemon.
### END INIT INFO

mjackson

/**
 * Converts an RGB color value to HSL. Conversion formula
 * adapted from http://en.wikipedia.org/wiki/HSL_color_space.
 * Assumes r, g, and b are contained in the set [0, 255] and
 * returns h, s, and l in the set [0, 1].
 *
 * @param   Number  r       The red color value
 * @param   Number  g       The green color value
 * @param   Number  b       The blue color value
 * @return  Array           The HSL representation

olasitarska

# -*- coding: utf-8 -*-
"""
Builds epub book out of Paul Graham's essays: http://paulgraham.com/articles.html

Author: Ola Sitarska <ola@sitarska.com>
Copyright: Licensed under the GPL-3 (http://www.gnu.org/licenses/gpl-3.0.html)

This script requires python-epub-library: http://code.google.com/p/python-epub-builder/
"""