using uCalcSoftware;

var uc = new uCalc();
var t = new uCalc.Transformer();
t.FromTo("A", "B").RewindOnChange = true;
t.FromTo("B", "C").RewindOnChange = true;
t.FromTo("C", "D").RewindOnChange = true;

uCalc.String trace = t.TraceTransform("A");

// Apply a custom format to each step in the list
trace.ListFormat("!", "(", ")", "$'{txt}->{n+1}/{c}'", "txt", "n", "c");

Console.WriteLine(trace);