Imports System
Imports uCalcSoftware
Public Module Program
   Public Sub Main()
      Dim uc As New uCalc()
      '// By default, invalid operations return 'nan'
      Console.WriteLine(uc.EvalStr("sqrt(-1)"))
      
      '// Enable error raising for this specific case
      uc.Error.TrapOnInvalid = true
      
      '// Now, the same operation returns a descriptive error message
      Console.WriteLine(uc.EvalStr("sqrt(-1)"))
   End Sub
End Module