assert_structure: Display an error if not the correct structure

In ChadGoymer/msgr: Extends Messages, Warnings and Errors by Adding Levels and Log Files

Description

This function calls the error() function to display an error if the structure of the input is not correct.

Usage

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

assert_names(
  x,
  names = NULL,
  level = 1,
  msg_level = getOption("msgr.level"),
  msg_types = getOption("msgr.types"),
  log_path = getOption("msgr.log_path")
)

assert_length(
  x,
  n = NULL,
  n_min = NULL,
  n_max = NULL,
  level = 1,
  msg_level = getOption("msgr.level"),
  msg_types = getOption("msgr.types"),
  log_path = getOption("msgr.log_path")
)

Arguments

x	(any) The object to test.
level	(integer, optional) The level of the message, 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	(character, 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".
names	(character) The allowed names.
n	(integer, optional) The allowed length.
n_min	(integer, optional) The minimum allowed length.
n_max	(integer, optional) The maximum allowed length.

Details

The following structures can be checked:

• assert_empty(): 'x' must be empty or NULL.

• assert_names(): 'x' must have names and optionally have the specified names.

• assert_length(): 'x' must have valid length. You can specify the exact length using n or the minimum and/or maximum length using n_min and n_max respectively.

Value

If assertion passes then TRUE is returned. This allows you to make multiple assertions separated by &.

Examples

## Not run: 

# No error
assert_empty(NULL)
assert_empty(integer())
# Error
assert_empty(1)

# No error
assert_names(c(name = "Bob", age = 42))
assert_names(c(name = "Bob", age = 42), names = c("name", "age"))
# Error
assert_names(c(name = "Bob", age = 42), names = c("name", "email"))

# No error
assert_length(1:3, n = 3)
assert_length(1:3, n_min = 1)
assert_length(1:3, n_min = 1, n_max = 10)
# Error
assert_length(1:3, n = 1)
assert_length(1:3, n_min = 5)
assert_length(1:3, n_min = 1, n_max = 2)


## End(Not run)

ChadGoymer/msgr documentation built on April 10, 2021, 10:31 a.m.