Re your follow-up question, which I seem unable to reply directly to:

If I follow, maybe workaround with something like this

Private Type uType
a As Long
b As String
End Type

Private muRec As uType
Private mbUseRec As Boolean

Sub Test1()
Dim n As Long, s As String
n = 123
s = "ABC"
MsgBox foo(n, s)
End Sub

Sub Test2()
Dim n As Long, s As String
Dim uRec As uType

With uRec
.a = 456
.b = "XYZ"
End With

muRec = uRec
mbUseRec = True

MsgBox foo(n, s)
mbUseRec = False ' < don't forget

End Sub

Function foo(n As Long, s As String) As String
If mbUseRec Then
With muRec
foo = .a & .b
End With
Else
foo = n & s
End If

End Function

FWIW I wouldn't do it like that myself!

Regards,
Peter T