using uCalcSoftware;

var uc = new uCalc();
var t = uc.NewTransformer();

t.FromTo("start {etc} end", "<{@Self}>");
t.FromTo("start2 {etc~} end", "<{@Self}>");

Console.WriteLine(t.Transform("start start2 a b c end end"));
Console.WriteLine(t.Transform("start2 start a b c end end"));