printf: Functions for Formatted Output and Conditions

In mlr3misc: Helper Functions for 'mlr3'

Functions for Formatted Output and Conditions

Description

catf(), messagef(), warningf() and stopf() are wrappers around base::cat(), base::message(), base::warning() and base::stop(), respectively.

Usage

catf(msg, ..., file = "", wrap = FALSE)

messagef(msg, ..., wrap = FALSE, class = NULL)

warningf(msg, ..., wrap = FALSE, class = NULL)

stopf(msg, ..., wrap = FALSE, class = NULL)

Arguments

msg	(character(1)) Format string passed to base::sprintf().
...	(any) Arguments passed down to base::sprintf().
file	(character(1)) Passed to base::cat().
wrap	(integer(1) | logical(1)) If set to a positive integer, base::strwrap() is used to wrap the string to the provided width. If set to TRUE, the width defaults to 0.9 * getOption("width"). If set to FALSE, wrapping is disabled (default). If wrapping is enabled, all whitespace characters (⁠[[:space:]]⁠) are converted to spaces, and consecutive spaces are converted to a single space.
class	(character()) Class of the condition (for errors and warnings).

Details

For leanified R6 classes, the call included in the condition is the method call and not the call into the leanified method.

Errors and Warnings

Errors and warnings get the classes ⁠mlr3{error, warning}⁠ and also inherit from ⁠simple{Error, Warning}⁠. It is possible to give errors and warnings their own class via the class argument. Doing this, allows to suppress selective conditions via calling handlers, see e.g. globalCallingHandlers.

When a function throws such a condition that the user might want to disable, a section Errors and Warnings should be included in the function documention, describing the condition and its class.

Examples

messagef("
  This is a rather long %s
  on multiple lines
  which will get wrapped.
", "string", wrap = 15)

mlr3misc documentation built on Sept. 13, 2025, 1:10 a.m.