FUNCTION Main()
   LOCAL aData, i, nPos

   // Array operations
   ? "=== Array Test ==="
   aData := {10, 30, 20, 50, 40}
   ? "Original:", Len(aData), "items"

   AAdd(aData, 60)
   ? "After AAdd:", Len(aData), "items"

   ASort(aData)
   ? "Sorted:"
   FOR i := 1 TO Len(aData)
      ? "  [" + Str(i) + "]", aData[i]
   NEXT

   nPos := AScan(aData, 30)
   ? "AScan(30) found at:", nPos

   ? "ATail:", ATail(aData)

   // String operations
   ? ""
   ? "=== String Test ==="
   ? Upper("hello world")
   ? Lower("HELLO WORLD")
   ? AllTrim("  spaces  ")
   ? Replicate("*", 10)
   ? PadR("Left", 15) + "|"
   ? PadL("Right", 15) + "|"

   // Type checking
   ? ""
   ? "=== Type Test ==="
   ? "ValType(42):", ValType(42)
   ? "ValType('abc'):", ValType("abc")
   ? "ValType(.T.):", ValType(.T.)
   ? "ValType(NIL):", ValType(NIL)
   ? "ValType({}):", ValType({})
   ? "Empty(''):", Empty("")
   ? "Empty(0):", Empty(0)
   ? "Empty('x'):", Empty("x")

   // Date
   ? ""
   ? "=== Date Test ==="
   ? "Time:", Time()
   ? "Seconds:", Seconds()

   ? ""
   ? "All tests passed!"
   RETURN NIL