lorentey

Noncopyable Standard Library Primitives

• Proposal: SE-NNNN
• Authors: Karoy Lorentey
• Review Manager: TBD
• Status: Awaiting review
• Roadmap: [Improving Swift performance predictability: ARC improvements and ownership control][Roadmap]
• Implementation:
  • The type/function generalizations are (provisionally) already present on main and release/6.0.

• The proposed API additions are implemented by PRs #73807 (main) and #73810 (release/6.0).

lorentey

// swift-tools-version:5.3
import PackageDescription
let package = Package(
  name: "countdown-solver",
  products: [
    .executable(name: "countdown-solver", targets: ["countdown-solver"]),
  ],
  dependencies: [
    .package(url: "https://github.com/apple/swift-argument-parser", from: "0.3.0"),
  ],

lorentey

Low-Level Atomic Operations ⚛︎

• Author: Karoy Lorentey
• Version: 2020-04-13/1
• Document URL: https://gist.github.com/lorentey/cf8703b5974ebe8f85cfb92a6628880d
• Forum Thread: https://forums.swift.org/t/low-level-atomic-operations/34683
• Implementation:
  • [swiftlang/swift#30553][implementation] (Atomic operations)
  • [swiftlang/swift#26969][constantPR] (Constant-constrained ordering arguments)

lorentey

Exposing the Memory Location of Class Instance Variables

Introduction

We propose to enable Swift code to retrieve the memory location of any directly addressable stored property in a class instance as an UnsafeMutablePointer value.

• Motivation
• Proposed Solution
• Efficiency Requirements
• Detailed Design

lorentey

Hello

This sample file contains examples of all kinds of data that can be stored in a pile.

All text up to the first line that consists of a #pile version directive is ignored by the parser.
Feel free to write anything here.

This is how all text piles start: (The "1" is the version number of the file format.)

#pile:1

lorentey

import Foundation

@objc class Person: NSObject {
    var _firstName: String = "John"
    var _lastName: String = "Smith"
    dynamic var firstName: String { get { return _firstName } set { _firstName = newValue } }
    dynamic var lastName: String { get { return _lastName } set { _lastName = newValue } }

    dynamic var name: String { return "\(firstName) \(lastName)" }

lorentey

protocol Sink {
    associatedtype Value
    func receive(_ value: Value)
}

// This assumes Generalized Existentials are a thing
// https://github.com/apple/swift/blob/master/docs/GenericsManifesto.md#generalized-existentials
typealias AnySink<Value> = Any<Sink where .Value == Value>

protocol Source {

lorentey

protocol Sink {
    func receive()
}

protocol Source {
    associatedtype Value

    func subscribe(_ sink: Sink) -> Int
    func unsubscribe(_ token: Int)

lorentey

### Keybase proof

I hereby claim:

  * I am lorentey on github.
  * I am lorentey (https://keybase.io/lorentey) on keybase.
  * I have a public key whose fingerprint is 086D 2046 8C31 E936 754F  C0C7 E9EA 32A8 0FB2 7A3F

To claim this, I am signing this object:

lorentey

extension Array where Element: Comparable {
  func clamp(from lowerBound: Element, to upperBound: Element) -> Array {
    return self.map { min(upperBound, max(lowerBound, $0)) }
  }
}

let clamped = [0, 1, 2, 3, 4, 5, 6].clamp(from: 2, to: 4))