warning(..., call. = TRUE, immediate. = FALSE, noBreaks. = FALSE, domain = NULL)
suppressWarnings(expr)
getOption("warn") <= 0<="" code="">.=>
options(warn = 1)
.options("warn")
and on handlers established in the
executing code.If a condition object is supplied it should be the only argument, and further arguments will be ignored, with a message.
warning
signals a warning condition by (effectively) calling
signalCondition
. If there are no handlers or if all handlers
return, then the value of warn = getOption("warn")
is
used to determine the appropriate action. If warn
is negative
warnings are ignored; if it is zero they are stored and printed after
the top--level function has completed; if it is one they are printed
as they occur and if it is 2 (or larger) warnings are turned into
errors. Calling warning(immediate. = TRUE)
turns warn <= 0<="" code=""> into
warn = 1
for this call only.=>
If warn
is zero (the default), a read-only variable
last.warning
is created. It contains the warnings which can be
printed via a call to warnings
.
Warnings will be truncated to getOption("warning.length")
characters, default 1000, indicated by [... truncated]
.
While the warning is being processed, a muffleWarning
restart
is available. If this restart is invoked with invokeRestart
,
then warning
returns immediately.
An attempt is made to coerce other types of inputs to warning
to character vectors.
suppressWarnings
evaluates its expression in a context that
ignores all warnings.
stop
for fatal errors,
message
for diagnostic messages,
warnings
,
and options
with argument warn=
. gettext
for the mechanisms for the automated translation
of messages.
testit <- function() warning("testit")
testit() ## shows call
testit <- function() warning("problem in testit", call. = FALSE)
testit() ## no call
suppressWarnings(warning("testit"))
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