A basic attempt at recreating the Form SwiftUI component on macOS

LabeledContainer.swift

import SwiftUI

struct LabeledViewAlignment: AlignmentID {
    static func defaultValue(in context: ViewDimensions) -> CGFloat {
        context[.leading]
    }
}

extension HorizontalAlignment {
    static let labeledViewAlignment = HorizontalAlignment(LabeledViewAlignment.self)
}

struct LabeledView<Content: View>: View {
    var label: String
    var content: Content
    
    init(label: String, @ViewBuilder builder: () -> Content) {
        self.label = label
        self.content = builder()
    }
    
    var body: some View {
        HStack(alignment: .firstTextBaseline) {
            Text(label)
                .multilineTextAlignment(.trailing)
            content
                .alignmentGuide(.labeledViewAlignment) { dimensions in
                    dimensions[.leading]
                }
        }
    }
}

struct LabelModifier: ViewModifier {
    var label: String
    
    func body(content: Content) -> some View {
        LabeledView(label: label) {
            content
        }
    }
}

extension View {
    func labeled(_ label: String) -> some View {
        self.modifier(LabelModifier(label: label))
    }
}

struct LabeledContainer<Content: View>: View {
    var content: Content
    
    init(@ViewBuilder builder: () -> Content) {
        self.content = builder()
    }
    
    var body: some View {
        VStack(alignment: .labeledViewAlignment, spacing: 0) {
            content
        }
    }
}