i stuck with this problem,

Screenshot 2021-07-31 at 5.25.29 PM617×279 11.6 KB

i could read the text from text-file and index it but i could not update
I’m missing something

defmodule ReadText do
  def read_text_file(file_name) do
    case File.read(file_name) do
      {:ok, text} ->
        IO.puts("slice 1: #{String.slice(text, 3..8)}")
        slice1 = IO.gets("slice 1 to replace: ")
        String.replace(text, String.slice(text, 3..8), slice1, global: false)
        IO.puts("slice 2: #{String.slice(text, 72..80)}")
        slice2 = IO.gets("slice 2 to replace: ")
        String.replace(text, String.slice(text, 72..80), slice2, global: false)
        IO.puts("slice 3: #{String.slice(text, 86..91)}")
        slice3 = IO.gets("slice 3 to replace: ")
        String.replace(text, String.slice(text, 86..91), slice3, global: false)
        IO.puts("slice 4: #{String.slice(text, 101..110)}")
        slice4 = IO.gets("slice 4 to replace: ")
        String.replace(text, String.slice(text, 101..110), slice4, global: false)

      {:error, error} ->
        IO.puts(error)
    end
  end

  def get_replaceable_indexs(file_name) do
    case File.read(file_name) do
      {:ok, text} ->
        text
        |> String.split("")
        |> Enum.with_index(fn v, i -> [i, v] end)

      {:error, error} ->
        IO.puts(error)
    end
  end

  def open(file_path) do
    File.open(file_path, [:read, :write], fn text ->
      IO.read(text, :all)
    end)
  end
end

i tried in livebook to get dynamic index for square brockets and use this index as rang in String.slice(text, 3..8) but i’m missing the logic

Screenshot 2021-07-31 at 9.01.41 PM490×933 48.5 KB

i highly appreciate any help
thank you