Usage

Wrap two children with SwapOff (default) and SwapOn. Clicking the container toggles state.

@actions.Swap(actions.SwapProps{
    InitialOn: false, // start in ON state
    Class:     "",    // extra classes on wrapper
}) {
    @actions.SwapOff() { <span>☀️ Light</span> }
    @actions.SwapOn()  { <span>🌙 Dark</span>  }
}