Type Printer
    tipo As String
    ink As Integer
End Type

Sub Printer_New(Byref p As Printer, Byval tipo As String, Byval ink As Integer)
    p.tipo = tipo
    p.ink = ink
End Sub

Function Printer_ink(Byref p As Printer) As Integer
    Return p.ink
End Function

Sub Printer_ink_Set(Byref p As Printer, Byval v As Integer)
    p.ink = v
End Sub

Sub Printer_print(Byref p As Printer, Byval text As String)
    Print p.tipo & ": ";
    For i As Integer = 1 To Len(text)
        Print Mid(text, i, 1);
    Next
    Print
    p.ink -= 1
End Sub

Dim Shared As Printer ptrMain, ptrReserve
Printer_New(ptrMain, "Main   ", 5)
Printer_New(ptrReserve, "Reserve", 5)

Dim Shared As String*44 hd(3) = {"Humpty Dumpty sat on a wall.", "Humpty Dumpty had a great fall.", "All the king's horses and all the king's men", "Couldn't put Humpty together again."}
Dim Shared As String*26 mg(7) = {"Old Mother Goose", "When she wanted to wander,", "Would ride through the air", "On a very fine gander.", "Jack's mother came in,", "And caught the goose soon,", "And mounting its back,", "Flew up to the moon."}

Function task(Byval nombre As String) As String
    Dim As Integer i
    Dim As String lines()
    If nombre = "Humpty Dumpty" Then
        Redim lines(Ubound(hd))
        For i = 0 To Ubound(hd) : lines(i) = hd(i)
        Next
    Else
        Redim lines(Ubound(mg))
        For i = 0 To Ubound(mg) : lines(i) = mg(i)
        Next
    End If

    For i = 0 To Ubound(lines)
        If Printer_ink(ptrMain) > 0 Then
            Printer_print(ptrMain, lines(i))
        Elseif Printer_ink(ptrReserve) > 0 Then
            Printer_print(ptrReserve, lines(i))
        Else
            Return "ERROR  : Reserve printer ran out of ink in " & nombre & " task."
        End If
    Next
    Return ""
End Function

Dim As String rhymes(1) = {"Humpty Dumpty", "Mother Goose"}
Dim As String tasks(1)

For i As Integer = 0 To 1
    tasks(i) = task(rhymes(i))
    If tasks(i) <> "" Then Print tasks(i): Exit For
Next

Sleep