HighlightSwift 🎨

Syntax Highlighting in Swift and SwiftUI

Contents

Highlight

Convert any String of code into a syntax highlighted AttributedString

• 🔍 Automatic language detection
• 📚 Works with 50 common languages
• 🌈 Choose from 30 classic color themes
• 🧰 Built with highlight.js and JavaScriptCore
• 🖥️ Supported on iOS, iPadOS, macOS, and tvOS

CodeText

Drop-in replacement for the SwiftUI Text view

• 🔠 Supports most Text modifiers like .font()
• 🌗 Color theme syncs automatically with Dark Mode

How to

Highlight

Highlight is available as an environment value:

@Environment(\.highlight) var highlight

Alternatively, create a new instance. By default the previous 50 highlights are cached. Use 0 to completely disable cacheing.

let highlight = Highlight(cacheLimit: 50)

Convert a plain String of code into a syntax highlighted AttributedString:

let attributedText = try await highlight.attributed("print(\"Hello World\")")

The language: parameter sets a specific language, disabling automatic detection.

let attributedText = try await highlight.attributed(code, language: "swift")

The colors: parameter sets the highlight theme and the system color scheme:

let attributedText = try await highlight.attributed(code, colors: .dark(.solarFlare))

The full request function provides the detected language and other details:

let result: HighlightResult = try await highlight.request("print(\"Hello World\")")

//   HighlightResult(
//      attributedText: "...",
//      relevance: 5,
//      language: "swift",
//      languageName: "Swift?",
//      backgroundColor: #1F2024FF,
//      hasIllegal: false,
//      isUndefined: false
//  )

CodeText

Create a CodeText view:

CodeText("print(\"Hello World\")")

Typical Text modifiers like .font() can be applied:

CodeText("print(\"Hello World\")")
    .font(.system(.callout, weight: .semibold))

The .codeTextTheme(_:) modifier sets one of the 30 built-in color themes. Each theme has a dark color scheme variant that is used automatically in Dark Mode:

CodeText("print(\"Hello World\")")
    .codeTextTheme(.github)

The .codeTextLanguage(_:) modifier sets a specific language, disabling automatic detection:

CodeText("print(\"Hello World\")")
    .codeTextLanguage(.swift)

The optional result binding provides the detected language, background color and other details:

@Binding var result: HighlightResult?

var body: some View {
    CodeText("print(\"Hello World\")", result: $result)
}

Installation

Project

1. In Xcode, go to File > Add packages...
2. Enter https://github.com/appstefan/highlightswift in the field and click Add Package

Package

In Package.swift add this repository as a dependency:

dependencies: [
    .package(url: "https://github.com/appstefan/highlightswift.git", from: "1.0.0")
],
targets: [
    .target(
        name: "YourPackageName",
        dependencies: ["HighlightSwift"]
    )
]

Author

Stefan, [email protected]

License

HighlightSwift is available under the MIT license. See the LICENSE.md file.

Highlight.js is available under the BSD license. See the LICENSE.md file.