error {msgr}

Display an error, and record it in a log file.

Description

error() is similar to stop(), but it also writes the error to a log file. Whether it is shown, or written to the log, depends on the level and type of the error. See details below for more information.

Usage

error(
  ...,
  level = 1,
  msg_level = getOption("msgr.level"),
  msg_types = getOption("msgr.types"),
  log_path = getOption("msgr.log_path")
)

Arguments

...

(strings) error to be displayed or written to file.

level

(integer, optional) The level of the error, from 1 to 10. Default: 1.

msg_level

(integer, optional) The maximum level of messages to output. Default: set in the option "msgr.level".

msg_types

(character, optional) The type to write or display. Must either NULL or one or more from "INFO", "WARNING" or "ERROR". Default: set in the option "msgr.types".

log_path

(string, optional) The file path to the text log file. If set to "", then no logs are written. Default: set in the option "msgr.log_path".

Details

Whether an error is shown, or written to the log, depends on two options:

1. Level: This allows control over the depth of messages. Each message can be assigned a level and if it is below the msg_level (set in the package option msgr.level by default) the message is displayed and written to the log.

2. Type: The type is refers to whether the message is "INFO", "WARNING" or "ERROR", as produced by the functions info(), warn() and error() respectively. If the message type is in the msg_types (set in the package option msgr.types by default) the message is displayed and written to the log. This allows you to for instance, just display errors and warnings and ignore messages.

The location of the log file is set in the package option msgr.log_path, or as an argument to this function. messages are added with a time stamp. If the log_path is equal to "" then no log is produced.

Value

A string is return invisibly containing the error

Examples

## Not run: 
  # Use error() to create timed errors
  error("This is a simple error")
  error("This is a level 2 error, so not shown by default", level = 2)

  # Set default level in options to determine what is shown
  options(msgr.level = 2)
  error("This is a level 2 error, so is shown now", level = 2)

## End(Not run)