message {base} | R Documentation |
Diagnostic Messages
Description
Generate a diagnostic message from its arguments.
Usage
message(..., domain = NULL, appendLF = TRUE)
suppressMessages(expr, classes = "message")
packageStartupMessage(..., domain = NULL, appendLF = TRUE)
suppressPackageStartupMessages(expr)
.makeMessage(..., domain = NULL, appendLF = FALSE)
Arguments
... |
zero or more objects which can be coerced to character
(and which are pasted together with no separator) or (for
|
domain |
see |
appendLF |
logical: should messages given as a character string have a newline appended? |
expr |
expression to evaluate. |
classes |
character, indicating which classes of messages should be suppressed. |
Details
message
is used for generating ‘simple’ diagnostic
messages which are neither warnings nor errors, but nevertheless
represented as conditions. Unlike warnings and errors, a final
newline is regarded as part of the message, and is optional.
The default handler sends the message to the
stderr()
connection.
If a condition object is supplied to message
it should be
the only argument, and further arguments will be ignored, with a warning.
While the message is being processed, a muffleMessage
restart
is available.
suppressMessages
evaluates its expression in a context that
ignores all ‘simple’ diagnostic messages.
packageStartupMessage
is a variant whose messages can be
suppressed separately by suppressPackageStartupMessages
. (They
are still messages, so can be suppressed by suppressMessages
.)
.makeMessage
is a utility used by message
, warning
and stop
to generate a text message from the ...
arguments by possible translation (see gettext
) and
concatenation (with no separator).
See Also
warning
and stop
for generating warnings
and errors; conditions
for condition handling and
recovery.
gettext
for the mechanisms for the automated translation
of text.
Examples
message("ABC", "DEF")
suppressMessages(message("ABC"))
testit <- function() {
message("testing package startup messages")
packageStartupMessage("initializing ...", appendLF = FALSE)
Sys.sleep(1)
packageStartupMessage(" done")
}
testit()
suppressPackageStartupMessages(testit())
suppressMessages(testit())