j-f1/forked-awesome-function-builders

A list of cool DSLs made with Swift 5.1’s @functionBuilder

awesome-function-builders

A list of cool DSLs made with Swift 5.1’s @functionBuilder

Currently, you instead have to use @_functionBuilder as it is a private implementation. This will change in the future, however.

Feel free to contribute if you make or find something awesome.

Contents

• The Proposal (SE-XXXX)

  The proposal has not been fully implemented in the current Xcode betas, which provide a simpler transformation than specified.

• Guides

• Projects

  • Dependency Injection
  • GraphQL
  • HTML
  • Networking
  • NSAttributedString
  • REST
  • SwiftUI
  • Testing
  • UIKit
  • Other

Guides

A list of helpful guides/tutorials on function builders

• Crash course in Swift's 'function builders' with SwiftUI
• Inside SwiftUI's Declarative Syntax's Compiler Magic
• The Swift 5.1 features that power SwiftUI’s API
• Create Your First Function Builder in 10 Minutes

Dependency Injection

• DependencyInjection - Dependency injection with function builders and property wrappers

DIContainer.register {
  New(MediaPlayer() as MediaplayerProtocol)
  New { _, id in ArticleViewModel(id: id) as PageViewModelProtocol }
  Shared(Router.init, as: RouterProtocol.self, DeeplinkHandler.self)
}

GraphQL

• Artemis - Interact with GraphQL in Swift - not strings

Operation(.query) {
  Add(\.country, alias: "canada") {
    Add(\.name)
    Add(\.continent) {
      Add(\.name)
    }
  }.code("CA")
}

• graphique - Experimental GraphQL query builders

query("") {
  hero {
    \.name
    lens(\.friends) {
      \.name
    }
  }
}

• Graphiti - Swift GraphQL Schema/Type framework for macOS and Linux

Schema<StarWarsAPI, StarWarsStore> {
  Enum(Episode.self) {
    Value(.newHope)
      .description("Released in 1977.")
    Value(.empire)
      .description("Released in 1980.")
    Value(.jedi)
      .description("Released in 1983.")
  }
  .description("One of the films in the Star Wars Trilogy.")
  ...
}

• SociableWeaver - Build declarative GraphQL queries in Swift.

Weave(.query) {
    Object(Post.self) {
        Field(Post.CodingKeys.title)

        Object(Post.CodingKeys.author) {
            Field(Author.CodingKeys.id)
            Field(Author.CodingKeys.name)
                .argument(key: "lastName", value: "Doe")
        }

        Object(Post.CodingKeys.comments) {
            Field(Comment.CodingKeys.id)
            Field(Comment.CodingKeys.content)
        }
        .argument(key: "filter", value: CommentFilter.recent)
    }
}

• ...

HTML

• HTML-DSL - A DSL for writing HTML in Swift

html(lang: "en-US") {
  body(customData: ["hello":"world"]) {
    article(classes: "readme", "modern") {
      h1 {
        "Hello World"
      }
    }
  }
}

• Vaux - A HTML DSL library for Swift

html {
  body {
    link(url: url, label: "Google", inline: true)
  }
}

• ...

Networking

• swift-request - Declarative HTTP networking, designed for SwiftUI

Request {
  Url("https://jsonplaceholder.typicode.com/todo")
  Header.Accept(.json)
}
.onData { ... }

let myJson = Json {
  JsonProperty(key: "firstName", value: "Carson")
}
myJson["firstName"].string // "Carson"

• ...

NSAttributedString

• NSAttributedStringBuilder - Composing NSAttributedString with SwiftUI-style syntax

NSAttributedString {
  AText("Hello world")
    .font(.systemFont(ofSize: 24))
    .foregroundColor(.red)
  LineBreak()
  AText("with Swift")
     .font(.systemFont(ofSize: 20))
     .foregroundColor(.orange)
}

• ...

REST

• Corvus – Building RESTful APIs with a declarative syntax.

var api = Api {
    BasicAuthGroup<User>("login") { login }
    JWTAuthGroup<User.Payload> {
        Group("users") { users }
        Group("inventory") {
            Group("articles") { articles }
        }
    }
}

• ...

SwiftUI

• ControlFlowUI - A library that add control flow functionality to SwitUI, using the power of @functionBuilder and ViewBuilder

List(dogs.identified(by: \.name)) { dog in
  SwitchValue(dog) {
    CaseIs(Animal.self) { value in
      Text(value.species)
    }
    CaseIs(Dog.self) { value in
      Text(value.breed)
    }
  }
}

• PathBuilder - Implementation of function builder for SwiftUI Path.

Path {
  Move(to: CGPoint(x: 50, y: 50))
  Line(to: CGPoint(x: 100, y: 100))
  Line(to: CGPoint(x: 0, y: 100))
  Close()
}

• SwiftWebUI - A demo implementation of SwiftUI for the Web

VStack {
  Text("🥑🍞 #\(counter)")
    .padding(.all)
    .background(.green, cornerRadius: 12)
    .foregroundColor(.white)
    .tapAction(self.countUp)
}

Testing

• Rorschach - Write Xcode UI Tests BDD style 🤷🏻‍♂️

expect(in: &context) {
  Given {
    ILearnABitMore()
    IBuildARocket()
  }
  When {
    ILaunchARocket()
  }
  Then {
    ICanSeeTheStars()
  }
}

UIKit

• BoxLayout - [WIP] SwiftUI's interface like AutoLayout DSL

BoxCenter {
  BoxVStack {
    BoxElement { toggleView }
    BoxEmpty()
      .frame(height: 20)
    if flag {
      BoxElement { top }
        .aspectRatio(ratio: CGSize(width: 1, height: 1))
    }
  }
}

• LegoKit

Lego {
  ForIn(3...4) { x in
    Section(layout:FlowLayout(col: x)) {
      ForIn(0...(x + 3)) { y in
        ImageItem(value: UIImage(named: "\(y % 2)")!)
      }
    }
  }
}

• Mockingbird - An experiment of implementing a UI layout and rendering framework inspired by SwiftUI

var content: some Node {
  VerticalStack {
    Repeated(0..<count) {
      Button(action: { self.count += 1 }) {
        BoxedText()
      }
    }
  }
  .cornerRadius(20)
  .animation(.spring)
}

• TurtleBuilder - Turtle graphics made on the top of Swift's function builder. It allows you to use a Logo-like syntax to create and draw lines in your Swift project.

let turtle = Turtle {
  penDown()
  loop(9) {
      left(140)
      forward(30)
      left(-100)
      forward(30)
  }
  penUp()
}

• ...

Other

• Pappe - A Proof of concept embedded interpreted synchronous DSL for Swift.

let m = Module { name in
    activity (name.Wait, [name.ticks]) { val in
        exec { val.i = val.ticks as Int }
        whileRepeat(val.i > 0) {
            exec { val.i -= 1 }
            await { true }
        }
    }
    activity (name.Main, []) { val in
        cobegin {
            strong {
                doRun(name.Wait, [10])
            }
            weak {
                loop {
                    doRun(name.Wait, [2])
                    exec { print("on every third") }
                    await { true }
                }
            }
            weak {
                loop {
                    doRun(name.Wait, [1])
                    exec { print("on every second") }
                    await { true }
                }
            }
        }
        exec { print("done") }
    }
}

• ...