# Using the Swift Playgrounds

## Getting Started

This GitBook page gives an overview of the available Swift Playgrounds, their intention and some initial motivation on why I created these. As the playgrounds are self-documented making extensive use of Markdown I advise you to jump into a topic and deep-dive in the calm seas of those playgrounds.

Please feel free to copy, share, and re-use the playgrounds as I always include an "I don't care" copyright, so I'm happy to donate my findings and results to the comunity without any loopholes. If you like you might mention where you stumbled across the idea and you might cite the original author(s), but that's certainly not a must.

## Using the Playgrounds

All playgrounds are hosted and published on [GitHub](https://github.com/MatiMax/swift-playgrounds). So please feel free to either clone or fork them. If you want to see some additions you might write a comment and ask for such. If you have some suggestions for improvements, please feel free to write a comment or modify the code, and thereafter post a pull request.

| Swift Playground                 | Topic                                                                                                                                             |
| -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------- |
| DNSResolve5                      | Resolve host names from a given IP address using Apple’s Core Foundation with `CFHost`. This *won’t* resolve the host alias names, though         |
| Factorial                        | Very simple demo of a recursion algorithm in Swift                                                                                                |
| Function Call Mapping            | Demonstration of calling functions dynamically using a routing pattern                                                                            |
| IPHostAddressResolution5         | Resolve host names from a given IP address using GLibC’s standard networking C function `gethostbyaddr`. This *does* resolve the host alias names |
| IPHostAddressResolution5 SwiftUI | Same as `IPHostAddressResolution5` with a simple UI                                                                                               |
| Pulsating Custom Button          | A custom SwiftUI button with a blinking LED indicator mimicking buttons found on KORG’s synthesisers                                              |
| QR Code                          | How to platform-independently generate a bitmap QR code using Apple’s CoreImage `CIFilter`                                                        |
| QR Code iOS                      | Same as `QR Code`, specifically designed for i(Pad)OS                                                                                             |
| QR Code macOS                    | Same as `QR Code`, specifically designed for macOS                                                                                                |
| SpeedMaths                       | A simple example of using a list view with a custom row content view with field-exit handler and context-dependent colouring                      |
| Syntax Tree                      | Demonstration of a tree algorithm adapted to the Swift programming language                                                                       |
| Tail Recursion                   | Demonstration of the tail recursion algorithm adapted to the Swift programming language                                                           |
| Using Opaque Types               | Demonstration of using Swift opaque types                                                                                                         |
| Using Phantom Types              | Demonstration of using phantom types in Swift                                                                                                     |