runemadsen

Polymorphic Associations reversed

It's pretty easy to do polymorphic associations in Rails: A Picture can belong to either a BlogPost or an Article. But what if you need the relationship the other way around? A Picture, a Text and a Video can belong to an Article, and that article can find all media by calling @article.media

This example shows how to create an ArticleElement join model that handles the polymorphic relationship. To add fields that are common to all polymorphic models, add fields to the join model.

baopham

cdfmr

@implementation NSApplication (Relaunch)

- (void)relaunchAfterDelay:(float)seconds
{
	NSTask *task = [[[NSTask alloc] init] autorelease];
	NSMutableArray *args = [NSMutableArray array];
	[args addObject:@"-c"];
	[args addObject:[NSString stringWithFormat:@"sleep %f; open \"%@\"", seconds, [[NSBundle mainBundle] bundlePath]]];
	[task setLaunchPath:@"/bin/sh"];
	[task setArguments:args];

cpjolicoeur

I'm hunting for the best solution on how to handle keeping large sets of DB records "sorted" in a performant manner.

Problem Description

Most of us have work on projects at some point where we have needed to have ordered lists of objects. Whether it be a to-do list sorted by priority, or a list of documents that a user can sort in whatever order they want.

A traditional approach for this on a Rails project is to use something like the acts_as_list gem, or something similar. These systems typically add some sort of "postion" or "sort order" column to each record, which is then used when querying out the records in a traditional order by position SQL query.

This approach seems to work fine for smaller datasets, but can be hard to manage on large data sets with hundreds (or thousands) of records needing to be sorted. Changing the sort position of even a single object will require updating every single record in the database that is in the same sort group. This requires potentially thousands of wri

brettfishman

# Given a controller that looks like this
class ModelsController < ApplicationController
  load_and_authorize_resource  #CanCan

  def show
    if stale? @model
      respond_to do |format|
        format.json do
          @model
        end

mbinna

#!/usr/bin/env bash

rm -rf "${HOME}/Library/Caches/CocoaPods"
rm -rf "`pwd`/Pods/"
pod update

dergachev

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

willurd

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

JamesDullaghan

How many servings should I eat per day?

• Fruit = 1-2 servings
• Animal protein = 4 - 6 servings
• Healthy fats = 5 - 9 servings
• Healthy vegetables = 6 - 11 servings

How should I allocate my calories per day?

• Healthy fats = 50%

aras-p

// Just before switching jobs:
// Add one of these.
// Preferably into the same commit where you do a large merge.
//
// This started as a tweet with a joke of "C++ pro-tip: #define private public",
// and then it quickly escalated into more and more evil suggestions.
// I've tried to capture interesting suggestions here.
//
// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,