Code/Core/Flow.cs
namespace Nodebox;

public enum Flow {
    Input,
    Output,
}
public static class PinTypeExtensions {
    extension(Flow flow) {
        public Flow Opposite => flow == Flow.Input ? Flow.Output : Flow.Input;
    }

    extension(PinIndex pinIndex) {
        public static PinIndex Invalid => PinIndex.MaxValue;
    }
}