Yannick Heinrich yageek

Swift Macros Dashboard

Macros are a power feature in a number of programming languages that make the language more extensible. Swift has always sought to enable expressive libraries through its use of type inference, generics, and general approach toward clarity of use. Macros in Swift are intended to improve expressiveness without sacrificing clarity.

This gist provides a "dashboard" with links to the various documents and example projects that are part of the Swift Macros effort. Head on over to the Swift Forums if you have questions!

Overview and examples:

Macros vision document: lays out the overall motivation, goals, and approach we're taking in the implementation of macros in Swift.
Example macros repository: contains a number of example macros that demonstrate the capabilities of the macro system and how it integrates into the language. This

Introduction

A JSON compilation database is a very handy output format which is parsed and used by many development tools. Unfortunately for us Apple Developers, it is not straightforward to generate one from within Xcode, as it is (probably) not Apple's priority and therefore there is no toggle/switch/setting that can be easily enabled to get this information.

There is however a solution, thanks to Apple using Clang/LLVM as their main toolchain.

Implementation

The standard way to generate this with clang would be to use the -MJ flag and give it a file name that typically corresponds to the input file. Using this flag indirectly through Xcode is hard, given that we're not aware of all the other arguments when a compiler call is executed.

However, there is a second hidden/badly documented LLVM flag: -gen-cdb-fragment-path - it is implemented in terms of -MJ and has the same functionality, but it's argument in contrast is an output directory.

	func scrollViewDidScroll(_ scrollView: UIScrollView) {
	for (i, view) in scrollView.subviews.enumerated() {
	var ty = 0.0
	if scrollView.contentOffset.y < 0 {
	// We're scrolling past the top of the scroll view.
	// Translate each item in the scroll view by some amount based on its index and scroll offset.
	ty = CGFloat(i) * abs(offsetY) / 8.0 * pow(1.12, CGFloat(i))
	}
	view.transform = CGAffineTransform(translationX: 0, y: ty)
	}

	# In the command line, find the PID of your simulator process:
	ps -p `pgrep launchd_sim`

	# or if you have many simulators running:
	ps -A \| grep launchd_sim

	# Find the PID of the WebContent process:
	pgrep -P <simulator-pid> 'com.apple.WebKit.WebContent'

	# kill it

	import SwiftUI

	struct ContentView: View {
	@State var horizontal: Bool = true
	@Namespace var namespace

	var body: some View {
	VStack(spacing: 40) {
	if horizontal {
	HStack { items }

	# Nicolas Seriot
	# 2021-09-17
	# 2021-09-18
	# https://gist.github.com/nst/032a61feb1fc60a74e13d2ea994763c0
	# Thread: https://twitter.com/nst021/status/1437889678947110912
	# Typical output: https://seriot.ch/visualization/iso4.png

	import cairo
	import random
	import numpy as np

	#![allow(unused)] // silence unused warnings while exploring (to comment out)

	use std::{error::Error, str};

	use s3::bucket::Bucket;
	use s3::creds::Credentials;
	use s3::region::Region;
	use s3::BucketConfiguration;

	// Youtube Walkthrough - https://youtu.be/uQKBW8ZgYB8

	// you need this in your cargo.toml
	// reqwest = { version = "0.11.3", features = ["stream"] }
	// futures-util = "0.3.14"
	// indicatif = "0.15.0"
	use std::cmp::min;
	use std::fs::File;
	use std::io::Write;

	use reqwest::Client;
	use indicatif::{ProgressBar, ProgressStyle};

	extension Data {
	init?(hexString: String) {
	let count = hexString.count / 2
	var data = Data(capacity: count)
	var i = hexString.startIndex
	for _ in 0 ..< count {
	let j = hexString.index(after: i)
	if var byte = UInt8(hexString[i ... j], radix: 16) {
	data.append(&byte, count: 1)
	} else {

	import Foundation

	public class Disposable {
	private var isDisposed = false
	private let _dispose: () -> Void
	public func dispose() {
	if !isDisposed {
	_dispose()
	isDisposed = true
	}