Format a log record by concatenating the log level, timestamp and message

  namespace = NA_character_,
  .logcall =,
  .topcall =,
  .topenv = parent.frame()



log level, see log_levels for more details


string message


string referring to the logger environment / config to be used to override the target of the message record to be used instead of the default namespace, which is defined by the R package name from which the logger was called, and falls back to a common, global namespace.


the logging call being evaluated (useful in formatters and layouts when you want to have access to the raw, unevaluated R expression)


R expression from which the logging function was called (useful in formatters and layouts to extract the calling function's name or arguments)


original frame of the .topcall calling function where the formatter function will be evaluated and that is used to look up the namespace as well via logger:::top_env_name


character vector

See also

This is a log_layout, for alternatives, see layout_blank, layout_glue, layout_glue_colors, layout_json, layout_json_parser, or generator functions such as layout_glue_generator