@spec bundle([{String.t(), String.t()}], map()) ::
  {:ok, String.t() | map()} | {:error, [String.t()]}

@spec collect_imports(String.t(), String.t()) ::
  {:ok, [map()]} | {:error, [String.t()]}

@spec imports(String.t(), String.t()) :: {:ok, [String.t()]} | {:error, [String.t()]}

@spec minify(String.t(), String.t(), map()) :: {:ok, String.t()} | {:error, list()}

@spec parse(String.t(), String.t()) :: {:ok, map()} | {:error, list()}

@spec transform(String.t(), String.t(), map()) ::
  {:ok, String.t() | map()} | {:error, list()}

@spec valid(String.t(), String.t()) :: boolean()