IsaacXen

import Foundation

public extension DispatchQueue {
    
    private struct _once_Domain: Hashable {
        /// The unique identifier for the class instance as domain.
        var identifier: ObjectIdentifier
        
        /// A weak reference to the class instance as domain.
        weak var lifetimeObject: NSObject?

IsaacXen

import UIKit

public extension NSCollectionLayoutAnchor {
    struct Offset {
        fileprivate var absolute: CGPoint?
        fileprivate var fractional: CGPoint?
        
        private init(absolute: CGPoint?, fractional: CGPoint?) {
            self.absolute = absolute
            self.fractional = fractional

IsaacXen

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IsaacXen

import Cocoa

protocol TextFieldDelegate: class {
    func textFieldDidBecomeFirstResponder(_ textField: TextField)
    func textFieldDidResignFirstResponder(_ textField: TextField)
}

class TextField: NSTextField {

    weak var firstResponderDelegate: TextFieldDelegate?