Brightscript string dupe checker

DupeChecker.brs

function DupeChecker() as Object

  this = {}
  this.dupes = []
  this.addItem = function(item as String, isPrintOnFoundDupe = false as Boolean) as Boolean
    isDupe = m.checkIsDupe(item)
    m.dupes.push(item)
    if isPrintOnFoundDupe then
      print item
    end if
    return isDupe
  end function

  this.checkIsDupe = function(item as String) as Boolean
    isDupe = false
    for i = 0 to m.dupes.count() - 1
      if m.dupes[i] = item then
        isDupe = true
      end if
    end for
    return isDupe
  end function

  this.clear = function() as Void
    m.dupes = Invalid
    m.dupes = []
  end function

  return this

end function