carson-katri

@_functionBuilder
struct AttributedStringBuilder {
  ...
  static func buildIf(_ segment: NSAttributedString?) -> NSAttributedString {
    segment ?? NSAttributedString()
  }
}

carson-katri

HStack {
  if greeting != nil {
    Text("\(greeting!) ")
  }
  Text("World")
}

carson-katri

NSAttributedString {
  "Hello "
    .foregroundColor(.red)
    .font(UIFont.systemFont(ofSize: 10.0))
  "World"
    .foregroundColor(.green)
    .underline(.orange, style: .thick)
}

carson-katri

extension String {
    func foregroundColor(_ color: UIColor) -> NSAttributedString {
        NSAttributedString(string: self, attributes: [.foregroundColor : color])
    }
    func background(_ color: UIColor) -> NSAttributedString {
        NSAttributedString(string: self, attributes: [.backgroundColor: color])
    }
    func underline(_ color: UIColor, style: NSUnderlineStyle = .single) -> NSAttributedString {
        NSAttributedString(string: self, attributes: [.underlineColor: color, .underlineStyle: style.rawValue])
    }

carson-katri

extension String {
    func colored(_ color: UIColor) -> NSAttributedString {
        NSAttributedString(string: self, attributes: [.foregroundColor : color])
    }
    func background(_ color: UIColor) -> NSAttributedString {
        NSAttributedString(string: self, attributes: [.backgroundColor: color])
    }
    func underline(_ color: UIColor, style: NSUnderlineStyle = .single) -> NSAttributedString {
        NSAttributedString(string: self, attributes: [.underlineColor: color, .underlineStyle: style.rawValue])
    }

carson-katri

extension NSAttributedString {
  convenience init(@AttributedStringBuilder _ content: () -> NSAttributedString) {
    self.init(attributedString: content())
  }
}

carson-katri

@_functionBuilder
struct AttributedStringBuilder {
  static func buildBlock(_ segments: NSAttributedString...) -> NSAttributedString {
    let string = NSMutableAttributedString()
    segments.forEach { string.append($0) }
    return string
  }
}

carson-katri

NSAttributedString {
    "Hello "
      .color(.red)
    "World"
      .color(.blue)
      .underline(.blue)
}

carson-katri

@_functionBuilder
struct GreetingBuilder {
    static func buildBlock(_ items: String...) -> [String] {
        return items.map { "Hello \($0)" }
    }
}

carson-katri

func combineWords() -> TupleView<(Text, Text)> {
  let _a = Text("Hello")
  let _b = Text("World")
  return ViewBuilder.buildBlock(_a, _b)
}