ChangeableCopy 1.0.0

ChangeableCopy 1.0.0

Maintained by Almazrafi.

  • By
  • Almaz Ibragimov


Build Status Codecov Cocoapods Carthage compatible SPM compatible Platforms Xcode Swift License

ChangeableCopy is a simple library that provides a convenient way to copy instances of Swift types with changed properties:

struct User: AutoChangeable {
    let id: Int
    let name: String
    let age: Int

let steve = User(id: 1, name: "Steve", age: 21)

// Copy the instance by changing the `name` and `age` properties
let steveJobs = steve.changing { newUser in = "Steve Jobs"
    newUser.age = 41


  • iOS 10.0+ / macOS 10.12+ / watchOS 3.0+ / tvOS 10.0+
  • Xcode 11.0+
  • Swift 5.1+


The most convenient way to use ChangeableCopy is to configure code generation and conform your structs to the AutoChangeable protocol:

struct User: AutoChangeable {
    let id: Int
    let name: String
    let age: Int

If you don't want to configure code generation, you just need to implement initialization from a copy manually:

extension User: Changeable {
    init(from copy: ChangeableCopy<Self>) {
            age: copy.age



CocoaPods is a dependency manager for Cocoa projects. You can install it with the following command:

$ gem install cocoapods

To integrate ChangeableCopy into your Xcode project using CocoaPods, specify it in your Podfile:

platform :ios, '10.0'

target '<Your Target Name>' do
    pod 'ChangeableCopy'

Finally run the following command:

$ pod install


Carthage is a decentralized dependency manager that builds your dependencies and provides you with binary frameworks. You can install Carthage with Homebrew using the following command:

$ brew update
$ brew install carthage

To integrate ChangeableCopy into your Xcode project using Carthage, specify it in your Cartfile:

github "almazrafi/ChangeableCopy" ~> 1.0.0

Finally run carthage update to build the framework and drag the built ChangeableCopy.framework into your Xcode project.

Swift Package Manager

The Swift Package Manager is a tool for managing the distribution of Swift code. It’s integrated with the Swift build system to automate the process of downloading, compiling, and linking dependencies.

To integrate ChangeableCopy into your Xcode project using Swift Package Manager, add the following as a dependency to your Package.swift:

.package(url: "", from: "1.0.0")

and then specify "ChangeableCopy" as a dependency of the Target in which you wish to use ChangeableCopy.

Here's an example Package.swift:

// swift-tools-version:5.0
import PackageDescription

let package = Package(
    name: "MyPackage",
    products: [
        .library(name: "MyPackage", targets: ["MyPackage"])
    dependencies: [
        .package(url: "", from: "1.0.0")
    targets: [
        .target(name: "MyPackage", dependencies: ["ChangeableCopy"])

Code generation

To generate code for the AutoChangeable protocol, the first thing you need to do is to install the Sourcery command line tool.

You can use a ready-made Stencil-template for Sourcery, which can be downloaded from the latest release files on the repository releases page.

If ChangeableCopy is installed using CocoaPods, it already contains this template and a helper script for generating code. You can either run it manually or in a custom build phase using the following command:

Pods/ChangeableCopy/Misc/AutoChangeable \
--sources Path/to/yours/sources \
--output Path/to/generated/file


  • If you need help, open an issue.
  • If you found a bug, open an issue.
  • If you have a feature request, open an issue.
  • If you want to contribute, submit a pull request.


ChangeableCopy is available under the MIT license. See the LICENSE file for more info.