There is the equivalent of /**/
of c # to comment and VBA instead of using plica in each row
'Function Prodcet30(a As Double, b As Double) As Double
'If a = 0 Then
' MsgBox ("Por favor introduza o valor a")
' Exit Sub
' Exit Sub
' End If
' If b = 0 Then
'MsgBox ("Por favor introduza o valor b")
' Exit Sub
'End If
' Prodcet30 = a * b
' End Function