Amzd

extension String? {
    /// This property is true on encountering one of "Y", "y", "T", "t", or a digit 1-9—the method ignores any trailing characters.
    /// This property is false if the receiver doesn’t begin with a valid decimal text representation of a number.
    ///
    /// The property assumes a decimal representation and skips whitespace at the beginning of the string. 
    /// It also skips initial whitespace characters, or optional -/+ sign followed by zeroes.
    var yN: Bool { if let self { NSString(string: self).boolValue } else { false } }
    /// This property is true when it is empty (or nil) or when yN is true
    var Yn: Bool { (self?.isEmpty ?? true) || yN }
}

Amzd

import UIKit

/// A view that hides its content to a user's recording, broadcast or screenshot.
/// https://gist.github.com/Amzd/2652bc98a6ae098701b342d710e45aa7
@available(iOS 12, *)
@dynamicMemberLookup
class PrivacySensitiveView<ContentView: UIView>: UIView {
    private var content: ContentView
    private var textField = {
        let textField = UITextField()

Amzd

extension UIViewController {
    /// UIDocumentPickerViewController by itself does not return first responder to the view controller that presented it
    /// when the cancel button is pressed after the search field was used. This function fixes that by making the previous
    /// first responder, first responder again when the document picker is dismissed.
    /// Normally this is handled by the private `UIViewController._restoreInputViewsForPresentation`
    /// but for some reason the UIDocumentPickerViewController does not call that, and since it's closed source I don't
    /// know why.
    ///
    /// To confirm this:
    /// - have a viewcontroller with a textfield

Amzd

extension Image {
    /// This helps achieving what `UIView.ContentMode.scaleAspectFit` and `.scaleAspectFill` do in UIImageView.contentMode
    ///
    /// The difference between Image.containerAspectRatio (this) and SwiftUIs View.aspectRatio is that the first applies the 
    /// aspect ratio to the view that contains the image, rather than to the image itself.
    ///
    /// So in the following example:
    /// - The first image will scale to a square but the contentMode does not do anything to prevent stretching and wether you use .fit or .fill does not matter.
    /// - The second image will resize to fit inside a square while maintaining its aspect ratio, similar to how a UIImageView with contentMode set to scaleAspectFit behaves.
    /// - The third image will resize to fill inside a square while maintaining its aspect ratio similar to how a UIImageView with contentMode set to scaleAspectFill behaves.

Amzd

protocol EmptyOrNil {
    var isEmpty: Bool { get }
}

extension Optional where Wrapped: EmptyOrNil {
    var isEmptyOrNil: Bool {
        return self?.isEmpty ?? true
    }
}

Amzd

import SwiftUI

/// Reads the width of the selection box next to a List row when editing mode is .active
///
/// Note: On iOS 15 the listRowInsets do not respond to updates so if you want to offset
/// the cell you should use negative leading padding.
public struct ListSelectionBoxWidthReader<Content: View>: View {
  @State private var boxWidth: CGFloat = 0
  private var content: (CGFloat) -> Content

Amzd

// Inspired by: https://gist.github.com/dfrib/d7419038f7e680d3f268750d63f0dfae
import Foundation

public extension Dictionary {

    subscript(keyPath string: Key, separator: String) -> Value? where Key == String {
        get { return self[keyPath: string.components(separatedBy: separator)] }
        set { self[keyPath: string.components(separatedBy: separator)] = newValue }
    }
    

Amzd

import Combine
import PublishedObject // https://github.com/Amzd/PublishedObject
import SwiftUI

/// A property wrapper type that instantiates an observable object.
@propertyWrapper
public struct StateObject<ObjectType: ObservableObject>: DynamicProperty
where ObjectType.ObjectWillChangePublisher == ObservableObjectPublisher {
    
    /// Wrapper that helps with initialising without actually having an ObservableObject yet

Amzd

import Foundation

extension Date {
    
    /// Returns date where **-component** is rounded to its closest
    /// multiple of **-amount**. Warning: month and day start at 1
    /// so round(to: 6, .month) will either return month 1 or 7!
    func round(to amount: Int, _ component: Calendar.Component) -> Date {
        let cal = Calendar.current
        var value = cal.component(component, from: self)

Amzd

// MARK: Appending closures `a + b`

/// Append closures, lhs first.
public func + <I>(lhs: @escaping (I) -> Void, rhs: @escaping (I) -> Void) -> ((I) -> Void) {
    return {
        lhs($0)
        rhs($0)
    }
}