gdavis

Xcode VIM

Learning VIM in Xcode comes with its own set of challenges and limitations, but there is enough there for you to give your mousing hand a break and master the keyboard.

A limited set of commands are available in Xcode, and this document attempts help ease the learning curve of using VIM in Xcode by providing a handy reference as well as what I find works for me in practice.

NOTE: Commands are case-sensitive. A command of N means pressing shift + n on the keyboard.

This document is a work in progress! Leave a comment if you would like to see a change.

nalexn

// Copyright © 2019 Alexey Naumov. MIT License

import Combine

typealias CancelBag = Set<AnyCancellable>

extension CancelBag {
    mutating func collect(@Builder _ cancellables: () -> [AnyCancellable]) {
        formUnion(cancellables())
    }

Winchariot

lazy var accessoryToolbarWithDoneButton: UIToolbar = {

    let toolbar = UIToolbar(frame: CGRect.zero)
    //only needs to be flexible in the dimension(s) you want it to be
    //https://stackoverflow.com/questions/31822504/how-can-i-increase-the-height-of-an-inputaccessoryview
    toolbar.autoresizingMask = [.flexibleWidth, .flexibleHeight] 
    
    let leftSpace = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
    let doneButton = UIBarButtonItem(barButtonSystemItem: .done, target: self, action: #selector(keyboardDoneButtonTapped(_:)))
    toolbar.items = [leftSpace, doneButton]

emarashliev

struct FailableDecodable<Base: Decodable>: Decodable {
    var base: Base?

    init(from decoder: Decoder) throws {
        let container = try decoder.singleValueContainer()
        do {
            base = try container.decode(Base.self)
        } catch let error {
            print(error)
        }

tclementdev

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

krin-san

typedef CF_ENUM(int, CFNetworkErrors) {

  kCFHostErrorHostNotFound = 1,
  kCFHostErrorUnknown = 2, // Query the kCFGetAddrInfoFailureKey to get the value returned from getaddrinfo; lookup in netdb.h
  // SOCKS errors; in all cases you may query kCFSOCKSStatusCodeKey to recover the status code returned by the server
  kCFSOCKSErrorUnknownClientVersion = 100,
  kCFSOCKSErrorUnsupportedServerVersion = 101, // Query the kCFSOCKSVersionKey to find the version requested by the server
  // SOCKS4-specific errors
  kCFSOCKS4ErrorRequestFailed = 110,  // request rejected or failed by the server
  kCFSOCKS4ErrorIdentdFailed = 111,  // request rejected because SOCKS server cannot connect to identd on the client

vukcevich

//: Playground - noun: a place where people can play

import UIKit

var str = "Anonymous Class in Swift"

//https://stackoverflow.com/questions/24408068/anonymous-class-in-swift
//There is no equivalent syntax.
//Regarding equivalent techniques, theoretically you could use closures and define structs and classes inside them.

magicien

import Foundation
import SceneKit

let json = """
{
    "position": [2.0, 5.0, 3.0],
    "rotation": [0.0, 0.73, 0.0, 0.73]
}
""".data(using: .utf8)!

lattner

Swift Concurrency Manifesto

Author: Chris Lattner

Chinese Translation by Jason Yu

Contents

• Introduction
• Overall Vision

mcmurrym

public extension CustomDebugStringConvertible {
    var debugDescription: String {
        return debugDescription()
    }
    
    func debugDescription(_ indentationLevel: Int = 0, includeType: Bool = true) -> String {
        
        let indentString = (0..<indentationLevel).reduce("") { tabs, _ in tabs + "\t" }
        
        var s: String