Sharing: Procedure to increment revision letter

Just wanted to share this little function for upping rev letter.

I created it as part of my attempt to automate much of our ECRN process and thought it might be useful to others.

I find it pretty handy, such as with a RevisionTableAnnotation object you can use it like:

REVTABLE.AddRevision (NextLetter(REVISION))

EDIT:  I updated code to fix a problem with transitioning from AAY to ABA.

EDIT 2:  I posted for peer review on CodeReview and received a much simpler method of doing this, so I've edited the code to this simplified version.

Link: vba - Next revision letter - Code Review Stack Exchange

Option Explicit
'***NOTE: _
    This module requires the following references: _
        <NONE>
        


Public Function NextRevLetter(currentRev As String) As String
    ' Alphabet, skipping I O Q S X Z
    Const alphabet As String = "ABCDEFGHJKLMNPRTUVWY"
    Dim i As Long
    Dim digit As String
    
    NextRevLetter = currentRev
    For i = Len(NextRevLetter) To 1 Step -1
        digit = Mid$(NextRevLetter, i, 1)
    
        ' Increment digit: "A"->"B", "B"->"C", ..., "H"->"J", ..., "Y"->"".
        ' Any other garbage maps to "A".
        digit = Mid$(alphabet, InStr(alphabet, digit) + 1, 1)
    
        If Len(digit) = 0 Then
            ' "Y"->"" case. Reset to "A", then carry.
            Mid$(NextRevLetter, i, 1) = "A"
        Else
            Mid$(NextRevLetter, i, 1) = digit
            Exit Function
        End If
    Next
    ' Carry.
    NextRevLetter = "A" & NextRevLetter
End Function

Message was edited by: Steve Soeder