Global rules

Set app defaultsCopy Anchor Link

Global rules inherit through the SwiftUI environment. They decorate views that use .tw and buttons that use its button style.

let rules = TWGlobalRules(
    view: "animate-smooth duration-200",
    button: "animate-spring duration-150",
    named: [
        "project-card": "card p-6 rounded-xl",
        "button-primary": "px-4 py-2 bg-primary text-primary-foreground rounded-lg"
    ]
)

ContentView().twRules(rules)

Use the recipe anywhere in that subtree:

VStack(alignment: .leading) {
    Text("Workspace").tw("text-lg font-semibold")
    Text("Three active projects").tw("text-sm text-muted-foreground")
}
.tw("project-card")

Local utilities override defaults by property. Rules do not decorate unstyled native views.

Override one subtreeCopy Anchor Link

SettingsView()
    .twRules { rules in
        rules.named["project-card"] = "card p-4 rounded-md"
    }

The closure updates inherited rules and keeps the remaining configuration. .twRules(rules) replaces the complete rules value for its subtree.

Custom argument utilitiesCopy Anchor Link

Register a prefix in global rules. Its factory receives a TWArgument and the current theme. The factory returns composable TWStyle values. Return nil to reject an argument.

let rules = TWGlobalRules(utilities: [
    "tilt": TWUtility { argument, _ in
        guard let degrees = argument.degrees else { return nil }
        return .rotate(degrees)
    },
    "inset": TWUtility { argument, theme in
        guard let units = argument.number, units >= 0,
              theme.space(CGFloat(units)).isFinite else { return nil }
        return .paddingPoints(theme.space(CGFloat(units)))
    }
])

Text("Hello")
    .tw("inset-[3] hover:tilt-[3deg] animate-smooth duration-[220ms]")
    .twRules(rules)

Argument helpers include number, points, seconds, degrees, components, and hexColor. Use rawValue for custom strings or argument grammars. Factories resolve against the nearest rules and theme when the view renders. Subtree overrides retain other inherited utility factories.

Exact named classes take precedence over factories. A registered prefix overrides the built-in bracket utility for that prefix. Factory output can contain named classes and state variants. Recursive output fails validation. These factories generate the styling properties that TWStyle supports. Register native modifier plugins through rules.modifiers for other SwiftUI modifiers.

Shared motion presetsCopy Anchor Link

let rules = TWGlobalRules(animations: [
    "settle": TWAnimation { duration in
        .spring(duration: duration, bounce: 0.15)
    }
])

Text("Details")
    .tw("card animate-settle duration-250")
    .twRules(rules)

Preset factories receive seconds. Class duration arguments use milliseconds unless they include an explicit unit. See animations.

Extend a built-in recipeCopy Anchor Link

Read the built-in definition when you replace that same recipe:

var rules = TWGlobalRules()
let base = TWStyle.defaultStyle(for: "button-primary")!
rules.named["button-primary"] = TWStyle(base, .rounded(.full), .minH(48))

Referencing .primaryButton inside its own replacement creates a cycle. The built-in definition preserves its existing sizing and state appearances.