keeshux/swon

Foundation-free Swift/JSON processing.

Usage

Dead easy. Attach the macro to any struct or enum:

import SWON

@SWON
enum Color {
	case red, green, blue
}

@SWON
struct Foobar {
	let numField: Int
	let stringArray: [String]
	let myDictionary: [String: [Double]]
	let innerStructs: [[CustomStruct]]
	let namedList: [Color]?
}

And you'll get a new initializer:

let foobar = try Foobar(fromJSON: """
{
	"numField": 100,
	"stringArray": ["one", "two", "three"]
	...
}
""")

Examples

The CMake configuration emits sample executables from the Swift files found in Examples. Run scripts/build.sh to generate them under the bin directory.

Why?

SWON is part of an ongoing "fight" against Swift dependencies [outside of the Apple ecosystem][web-cps], whose goal is making my app, [Passepartout][github-passepartout], natively cross-platform with Swift.

If you only use Swift on Apple platforms, you won't find this package very useful, if at all. JSONEncoder and JSONDecoder offer such a thorough feature set that SWON doesn't even try to replace them.

Instead, it serves the single purpose of parsing complex value types with a tiny footprint, because it doesn't rely on Foundation. In fact, SWON doesn't even use Codable, thus making it a future candidate for [Embedded Swift][swift-embedded], where Codable is unavailable.

Last but not least, it was an entertaining exercise to get familiar with [Swift Macros][swift-macros].

SWON uses the amazingly written [cJSON][credits-cjson] parser (C) under the hood.

Caveats

Restrictions

Dictionary keys must be String.
Optionals in collections (e.g. [Int?]) are not supported.
Nulls are not supported.

Things to do

Handle RawRepresentable automatically.
Do not suppress errors inside an optional field (silently made nil).
Add thorough tests and meaningful examples.
Clean up some messy code.

License

This project is licensed under the [MIT][license-content].

Contacts

Twitter: [@keeshux][about-twitter]

Website: [davidederosa.com][web-home], with my blog series on [cross-platform Swift][web-cps].

[license-content]: LICENSE [swift-macros]: https://docs.swift.org/swift-book/documentation/the-swift-programming-language/macros/ [swift-embedded]: https://www.swift.org/get-started/embedded/ [credits-cjson]: https://github.com/DaveGamble/cJSON [web-home]: https://davidederosa.com [web-cps]: https://davidederosa.com/cross-platform-swift/ [github-passepartout]: https://github.com/partout-io/passepartout [about-twitter]: https://twitter.com/keeshux

Package Metadata

Repository: keeshux/swon

Default branch: master

README: README.md