function Text.compute_fragments(State, line_index)

function Text.compute_fragments(State, line)

  local line = State.lines[line_index]
  local line_cache = State.line_cache[line_index]
  line_cache.fragments = {}

  local result = {}

        table.insert(line_cache.fragments, {data=frag1, text=frag1_text})

        table.insert(result, {data=frag1, text=frag1_text})

      table.insert(line_cache.fragments, {data=frag, text=frag_text})

      table.insert(result, {data=frag, text=frag_text})

  return result

    Text.compute_fragments(State, line_index)

    line_cache.fragments = Text.compute_fragments(State, line)