define a function alias in VBA, possible?

Would Run suit?

new_func = IIf(term, "foo1", "foo2")
''new_func arg1, arg2, arg3

res = Run(new_func, "a", "b", 1)

More information: http://msdn.microsoft.com/en-us/library/aa199108(office.10).aspx

If the 2 functions were implemented in 2 different class modules you could give them the same name & call them across an interface. That's about as close as you can get. (and its not very close)

'empty interface class, name: IFoo
Public Function TheFunc(i As Integer) As Long
'
End Function

'class clsFoo1
Implements IFoo

Private Function IFoo_TheFunc(i As Integer) As Long
MsgBox "I'm clsFoo1"
End Function

'class clsFoo2
Implements IFoo

Private Function IFoo_TheFunc(i As Integer) As Long
MsgBox "I'm clsFoo2"
End Function

'module code;
Dim myFoo As IFoo
If var = 1 Then
    Set myFoo = New clsFoo1
Else
    Set myFoo = New clsFoo2
End If

myFoo.TheFunc 12345