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//
// ContentView.swift
// AnimationTimingCurve
//
// Created by Chris Eidhof on 25.09.19.
// Copyright © 2019 Chris Eidhof. All rights reserved.
//
import SwiftUI
@DevAndArtist
DevAndArtist / reimplemented_parts_of_swiftui.swift
Last active May 29, 2023 14:55
This is a custom implementation of some parts of SwiftUI which I could observe.
import CoreGraphics
final class TransactionStack {
static let shared = TransactionStack()
private var _transactions: [Transaction]
private init() {
dispatchPrecondition(condition: .onQueue(.main))
_transactions = []
@AliSoftware
AliSoftware / Bindings.swift
Last active March 26, 2025 12:10
Re-implementation of @binding and @State (from SwiftUI) myself to better understand it
/*:
This is a concept re-implementation of the @Binding and @State property wrappers from SwiftUI
The only purpose of this code is to implement those wrappers myself
just to understand how they work internally and why they are needed,
⚠️ This is not supposed to be a reference implementation nor cover all
subtleties of the real Binding and State types.
The only purpose of this playground is to show how re-implementing
them myself has helped me understand the whole thing better
@niw
niw / how_to_extract_dylib_from_shared_cache.md
Last active April 15, 2025 13:10
How to extract dylib from shared cache

How to extract dylib from shared cache

To understand iOS behaviors, sometimes it’s important to disassemble iOS framework binaries.

Since recent iOS firmware, known as .ipsw file, contains non-encrypted root image, it’s easy to access these binaries. However, each framework binaries, dylib files, are placed in a shared cache file.

Thus, before disassembling it, we need to extract the one from the cache.

//Copyright (c) 2018 Michael Eisel. All rights reserved.
#import "CLRCallRecorder.h"
#import <dlfcn.h>
#import <libkern/OSAtomicQueue.h>
#import <pthread.h>
typedef struct {
void *ptr;
NSInteger number;
@rxwei
rxwei / ad-manifesto.md
Last active December 6, 2024 16:54
First-Class Automatic Differentiation in Swift: A Manifesto
@rnystrom
rnystrom / ViewController.swift
Created May 29, 2018 01:16
Interactive NSAttributedString link highlighting with TextKit
import UIKit
public extension CGSize {
func snapped(scale: CGFloat) -> CGSize {
var size = self
size.width = ceil(size.width * scale) / scale
size.height = ceil(size.height * scale) / scale
return size
}
@tclementdev
tclementdev / libdispatch-efficiency-tips.md
Last active May 9, 2025 09:50
Making efficient use of the libdispatch (GCD)

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

  • You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.

  • Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse

@anandabits
anandabits / HKT.swift
Last active December 25, 2023 00:57
Emulating HKT in Swift
// This example shows how higher-kinded types can be emulated in Swift today.
// It acheives correct typing at the cost of some boilerplate, manual lifting and an existential representation.
// The technique below was directly inspired by the paper Lightweight Higher-Kinded Polymorphism
// by Jeremy Yallop and Leo White found at http://ocamllabs.io/higher/lightweight-higher-kinded-polymorphism.pdf
/// `ConstructorTag` represents a type constructor.
/// `Argument` represents an argument to the type constructor.
struct Apply<ConstructorTag, Argument> {
/// An existential containing a value of `Constructor<Argument>`
/// Where `Constructor` is the type constructor represented by `ConstructorTag`
@ttrahan
ttrahan / block_personal_appts
Last active May 6, 2025 17:17
Google Apps Script to automatically create, edit and delete events on work calendar for personal calendar events. Instructions on how to set up can be found at https://medium.com/@willroman/auto-block-time-on-your-work-google-calendar-for-your-personal-events-2a752ae91dab
function sync() {
var id="XXXXXXXXXX"; // CHANGE - id of the secondary calendar to pull events from
var today=new Date();
var enddate=new Date();
enddate.setDate(today.getDate()+7); // how many days in advance to monitor and block off time
var secondaryCal=CalendarApp.getCalendarById(id);
var secondaryEvents=secondaryCal.getEvents(today,enddate);