FractionalIndex.generate_key_between

You're seeing just the function generate_key_between, go back to FractionalIndex module for more information.
Link to this function

generate_key_between(a, b)

Specs

generate_key_between(String.t() | nil, String.t() | nil) ::
  {:ok, String.t()} | {:error, FractionalIndex.Errors.error()}