(pat : String.Slice) →
  UInt8 →
    (table : Array ℕ) →
      table.size ≤ pat.utf8ByteSize →
        (∀ (i : ℕ) (hi : i < table.size), table[i] ≤ i) → (guess : ℕ) → guess < table.size → { n // n < table.size }