Selectively suppress messages, warnings, cat and print — suppress

Selectively suppress messages, warnings, cat and/or print whose output matches given regex pattern.

Usage

suppress_matching(
  expr,
  pattern = NULL,
  suppress_messages = TRUE,
  suppress_warnings = TRUE,
  suppress_cat_print = TRUE,
  ...
)

Arguments

expr

An expression that potentially produces some output.

pattern

Provide a regex-string to only suppress matching output. If NULL, suppresses all output.

suppress_messages

If output from message() shall be suppressed.

suppress_warnings

If output from warning() shall be suppressed.

suppress_cat_print

If output from cat() and print() shall be suppressed.

...

Arguments passed on to base::grepl

ignore.case: logical. if FALSE, the pattern matching is case sensitive and if TRUE, case is ignored during matching.
perl: logical. Should Perl-compatible regexps be used?
fixed: logical. If TRUE, pattern is a string to be matched as is. Overrides all conflicting arguments.
useBytes: logical. If TRUE the matching is done byte-by-byte rather than character-by-character. See ‘Details’.

Value

The return value of the expr.

Details

Utilizes grepl() for matching output with given regex pattern. Selective suppression of cat() and print() is tricky, as differentiation of single output is not trivial. This function applies a simple heuristic to at least separate print() output from each other and cat(). Two consecutive cat() outputs can not be differentiated at the moment, potentially leading to unwanted selective suppression behavior.

Examples

noisy_fun <- function() {
  message("I am a message")
  warning("I am a warning")
  cat("I am a cat")
  print("I am a print")
  return(TRUE)
}

# suppress all
result <- suppress_matching(noisy_fun())

# suppress by matching regex
result <- suppress_matching(noisy_fun(), pattern = ".*am A.*", ignore.case = TRUE)