https://twitter.com/inamiy/status/1428285236547260419

SwiftUI-pipe.swift

import SwiftUI

extension View {
    func pipe<R>(@ViewBuilder _ f: (Self) -> R) -> R {
        f(self)
    }
}

struct ContentView: View {
    @State var flag: Bool = false

    var body: some View {
        Rectangle()
            // 1. ternary conditional operator
            // .foregroundColor(flag ? .red : .blue)

            // 2. pipe
            .pipe {
                if flag {
                    $0.foregroundColor(.red)
                } else {
                    $0.foregroundColor(.blue)
                }
            }
            .onTapGesture {
                withAnimation {
                    flag.toggle()
                }
            }
            .padding()
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}