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mattt /
Created Nov 26, 2012
NSHipster Call for Tips & Tricks!

Howdy howdy, NSHipsters!

If you alloc init an NSCalendar, you'll notice that New Year's Eve falls on a Monday this year, a.k.a. "the day NSHipster is published every week". What fun!

So in celebration of the upcoming year++, I thought it'd be fun to compile a list of some of your favorite tips and tricks of the trade. Submit your favorite piece of Objective-C trivia, framework arcana, hidden Xcode feature, or anything else you think is cool, and you could have it featured in the year-end blowout article. Just comment on this gist below!

Here are a few examples of the kind of things I'd like to see:

romaonthego / NSDateFormatter cheat sheet
Last active Sep 16, 2020
Date Formats for NSDateFormatter
View NSDateFormatter cheat sheet
a: AM/PM
A: 0~86399999 (Millisecond of Day)
c/cc: 1~7 (Day of Week)
ccc: Sun/Mon/Tue/Wed/Thu/Fri/Sat
cccc: Sunday/Monday/Tuesday/Wednesday/Thursday/Friday/Saturday
d: 1~31 (0 padded Day of Month)
D: 1~366 (0 padded Day of Year)
stefanschmidt /
Created Aug 27, 2013
Stop Dropbox from asking for admin password after installation to ~/Applications
chmod 0000 ~/Applications/*.tgz
jtbandes / ConstraintCollection.swift
Created Feb 20, 2015
Autolayout constraint literals in Swift
View ConstraintCollection.swift
#if os(iOS)
import UIKit
import AppKit
/// A set of constraints prepared from a visual format string, in the style of
/// `NSLayoutConstraint.constraintsWithVisualFormat()`, with the additional ability
/// to supply views and metrics in a string interpolation.
chockenberry /
Last active Oct 22, 2020
A simple shell script to turn the Finders desktop icons on and off
defaults read CreateDesktop > /dev/null 2>&1
if [ "$1" = "off" ]; then
if [ $enabled -eq 1 ]; then
defaults write CreateDesktop false
osascript -e 'tell application "Finder" to quit'
open -a Finder
inamiy /
Last active Oct 5, 2020
React & Elm inspired frameworks in Swift
nubbel /
Created Jun 9, 2017 — forked from ddunbar/
Xcode new build system debugging tricks

New Build System Tricks

Command Line

# enable internal menu
defaults write ShowDVTDebugMenu -book YES

alias xcbuild=$(xcode-select -p)/../SharedFrameworks/XCBuild.framework/Versions/A/Support/xcbuild
View Class Clusters
As of iOS 11/macOS High Sierra, and only including ones in Foundation and CoreFoundation
_NSCFString - a CFStringRef or CFMutableStringRef. This is the most common type of string object currently.
- May have 8 bit (ASCII) or 16 bit (UTF-16) backing store
_NSCFConstantString - a compile time constant CFStringRef, like you'd get with @"foo"
- May also be generated by dynamic string creation if matches a string in a pre-baked table of common strings called the StringROM
NSBigMutableString - an NSString backed by a CFStorage ( for faster handling of very large strings
NSCheapMutableString - a very limited NSMutableString that allows for zero-copy initialization. Used in NSFileManager for temporarily wrapping stack buffers.
View ContentView.swift
// ContentView.swift
// Layout
// Created by Matt Gallagher on 7/6/19.
// Copyright © 2019 Matt Gallagher. All rights reserved.
import SwiftUI
dabrahams / FactoryInitialization.swift
Last active Sep 3, 2020
Class factory initializers
View FactoryInitialization.swift
/// Classes whose initializers actually create derived classes
protocol FactoryInitializable {
/// The type of the least-derived class declared to be FactoryInitializable.
/// - Warning: Do not define this in your FactoryInitializable type!
associatedtype FactoryBase: AnyObject, FactoryInitializable = Self
// This associatedtype is a trick that captures `Self` at the point where
// `FactoryInitializable` enters a class hierarchy; in other contexts, `Self`
// refers to the most-derived type.
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