Contents

CaptureContext/swift-foundation-extensions

Standard extensions for Foundation framework

Contents

Coding

  • RawCodingKey allows you to create CodingKeys from literals
  • Extensions for encoder and decoder allow you to create an object with a contextual container
  • Extensions for coding containers automatically infer type from context
init(from decoder: Decoder) throws {
  self = try container.decode(RawCodingKey.self) { container in
    return .init(
      someProperty1: container.decode("someProperty1"),
      someProperty2: container.decode("some_property_2")
    )
  }
}

func encode(to encoder: encoder) throws {
  try encoder.encode(RawCodingKey.self) { container in
    try container.encode(someProperty1, forKey: "someProperty1")
    try container.encode(someProperty2, forKey: "some_property_2")
  }
}

NSLocking

  • store(_:in:) - stores value in some variable in locked context
  • mutate(_:with:) - passes given object to locked context
  • assign(_:to:on:) - stores value in object property in locked context
  • execute(_:) - provides new locked context

Optional

  • orThrow(_:) - unwraps an optional or throws specified error
  • isNil / isNotNil / isNilOrEmpty
  • or() - coalesing alias
  • unwrap() - returns unwrapping Result
  • assign(to:on:) - assigns wrapped value to a specified target property by the keyPath
  • ifLetAssign(to:on:) - assigns wrapped value to a specified target property by the keyPath if an optional was not nil

Indirect

CoW container, which allows you to recursively include single instances of value types

struct ListNode<Value> {
  var value: Value
  
	@Indirect
  var next: ListNode<Value>?
}

PropertyProxy

class MyView: UIView {
  private let label: UILabel
  
  @PropertyProxy(\MyView.label.text)
  var text: String?
  
  @ReadonlyPropertyProxy(\MyView.label.text)
  var readonlyText: String?
}

let view: MyView = .init()
view.label.text // ❌
view.text = "Hello, World!"

Swizzling

This package also provides some sugar for objc method swizzling

[!NOTE]

The package is compatible with non-Apple platforms, however it uses conditional compilation, so Swizzling APIs are only available on Apple platforms

extension UIViewController {
  // Runs once in app lifetime
  // Repeated calls do nothing
  private static let swizzle: Void = {
    // This example is not really representative since these methods
    // can be simply globally overriden, but it's just an example
    // for the readme and you can find live example at
    // https://github.com/capturecontext/combine-cocoa-navigation
    
    objc_exchangeImplementations(
    	#selector(viewWillAppear)
      #selector(__swizzledViewWillAppear)
    )
    
    objc_exchangeImplementations(
    	#selector(viewDidAppear)
      #selector(__swizzledViewDidAppear)
    )
  }()

  @objc dynamic
  private func __swizzledViewWillAppear(_ animated: Bool) {
    __swizzledViewWillAppear(animated) // calls original method
    print(type(of: self), ObjectIdentifier(self), "will appear")
  }

  @objc dynamic
  private func __swizzledViewDidAppear(_ animated: Bool) {
    __swizzledViewDidAppear(animated) // calls original method
    print(type(of: self), ObjectIdentifier(self), "did appear")
  }
}

More

More extensions can be found in sources.

Equated

[!WARNING]

FoundationExtensions simply exports Equated for backwards compatibility

It's likely to be removed in favor of a separate package swift-equated, see it's readme for more info

Undo/Redo management

[!WARNING]

FoundationExtensions simply exports Resettable for backwards compatibility

It's likely to be removed in favor of a separate package swift-resettable, see it's readme for more info

Object Association

[!WARNING]

FoundationExtensions simply exports AssociatedObjects

FoundationExtensionsMacros simply exports AssociatedObjectsMacros

Likely to be removed in favor of a separate package swift-associated-objects

Installation

Basic

You can add swift-foundation-extensions to an Xcode project by adding it as a package dependency.

  1. From the File menu, select Swift Packages › Add Package Dependency…
  2. Enter "https://github.com/capturecontext/swift-foundation-extensions" into the package repository URL text field
  3. Choose products you need to link to your project.

Recommended

If you use SwiftPM for your project structure, add swift-foundation-extensions dependency to your package file

.package(
  url: "https://github.com/capturecontext/swift-foundation-extensions.git", 
  .upToNextMinor("0.7.0")
)

Do not forget about target dependencies

.product(
  name: "<#Product#>", 
  package: "swift-foundation-extensions"
)

License

This library is released under the MIT license. See LICENSE for details.

Package Metadata

Repository: CaptureContext/swift-foundation-extensions

Homepage: https://swiftpackageindex.com/CaptureContext/swift-foundation-extensions/0.4.2/documentation/foundationextensions

Stars: 19

Forks: 0

Open issues: 0

Default branch: main

Primary language: swift

License: MIT

Topics: associated-objects, associatedobject, async, coding, essentials, extensions, foundation, macros, runtime, spm, swift, swift-macro, swift-macros, swift-package-manager, swizzling, undo-redo

README: README.md