def evals_or_file
      # --library
      return if lib_only

      if evals.any?
        yield evals.join("\n"), '-e'
      elsif file && (filename != '-' || evals.empty?)
        yield file.read, filename
      end
    end
def evals_or_file
      # --library
      return if lib_only

      if evals.any?
        yield evals.join("\n"), '-e'
      elsif file && (filename != '-' || evals.empty?)
        yield file.read, filename
      end
    end
Internal: Yields a string of source code and the proper filename for either
           evals, stdin or a filepath.