ArrayBuilder

A result builder that allows to build arrays declaratively with conditions and loops with SwiftUI like syntax.

Inspired by https://gist.github.com/rjchatfield/72629b22fa915f72bfddd96a96c541eb

Usage

The usual way to create arrays with conditions:

    var textItems: [String] = []
    textItems.append("Lorem")
    if false {
        textItems.append("Amen")
    }
    if true {
        textItems.append("Ipsum")
    }
    textItems.append("Dolor")

Creating arrays with conditions using ArrayBuilder:

    let textItems: [String] = .init {
        "Lorem"
        if false {
            "Amen"
        }
        if true {
            "Ipsum"
        }
        "Dolor"
    }

Also supports switch case and for loops:

    let textItems: [String] = .init {
        "Lorem"
        
        switch number {
        case 5:
            "Ipsum"
        default:
            Void()
        }
        
        for number in 0...2 {
            "\(number)"
        }
        
        "Dolor"
    }

Using in a function that returns an array:

    @ArrayBuilder<String> func textItems() -> [String] {        
        "Lorem"
        if true {
            "Ipsum"
        }
        "Dolor"
    }

    let array = textItems()

Using in a function that takes an array as a parameter:

    func numberOfItems(@ArrayBuilder<String> _ array: () -> [String]) -> Int {
        return array().count
    }

    let count = numberOfItems {
        "Lorem"
        if false {
            "Amen"
        }
        if true {
            "Ipsum"
        }
        "Dolor"
    }
    // count == 3

Swift Package Manager

This library is a Swift Package and can be added using this URL:

https://github.com/WilhelmOks/ArrayBuilder.git

Import the module to use ArrayBuilder it in your code:

import ArrayBuilderModule

To use ArrayBuilder in the whole project without import in each file, you can create a typealias:

typealias ArrayBuilder = ArrayBuilderModule.ArrayBuilder