Existe existe um alcance de Excel VBA denominado

Function NamedRangeExist(ByRef pWorkBook As Workbook, pName As String) As Boolean
    Dim nName As Name
    For Each nName In pWorkBook.Names
        If nName.Name = pName Then
            NamedRangeExist = True
            Exit Function
        End If
    Next nName
End Function
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