| % File src/library/base/man/message.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2011 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{message} |
| \alias{message} |
| \alias{suppressMessages} |
| \alias{packageStartupMessage} |
| \alias{.packageStartupMessage} |
| \alias{suppressPackageStartupMessages} |
| \alias{.makeMessage} |
| \title{Diagnostic Messages} |
| \description{ |
| Generate a diagnostic message from its arguments. |
| } |
| \usage{ |
| message(\dots, domain = NULL, appendLF = TRUE) |
| suppressMessages(expr) |
| |
| packageStartupMessage(\dots, domain = NULL, appendLF = TRUE) |
| suppressPackageStartupMessages(expr) |
| |
| .makeMessage(\dots, domain = NULL, appendLF = FALSE) |
| } |
| \arguments{ |
| \item{\dots}{zero or more objects which can be coerced to character |
| (and which are pasted together with no separator) or (for |
| \code{message} only) a single condition object.} |
| \item{domain}{see \code{\link{gettext}}. If \code{NA}, messages will |
| not be translated, see also the note in \code{\link{stop}}.} |
| \item{appendLF}{logical: should messages given as a character string |
| have a newline appended?} |
| \item{expr}{expression to evaluate.} |
| } |
| \details{ |
| \code{message} is used for generating \sQuote{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 |
| \code{\link{stderr}()} \link{connection}. |
| |
| If a condition object is supplied to \code{message} it should be |
| the only argument, and further arguments will be ignored, with a warning. |
| |
| While the message is being processed, a \code{muffleMessage} restart |
| is available. |
| |
| \code{suppressMessages} evaluates its expression in a context that |
| ignores all \sQuote{simple} diagnostic messages. |
| |
| \code{packageStartupMessage} is a variant whose messages can be |
| suppressed separately by \code{suppressPackageStartupMessages}. (They |
| are still messages, so can be suppressed by \code{suppressMessages}.) |
| |
| \code{.makeMessage} is a utility used by \code{message}, \code{warning} |
| and \code{stop} to generate a text message from the \code{\dots} |
| arguments by possible translation (see \code{\link{gettext}}) and |
| concatenation (with no separator). |
| } |
| \seealso{ |
| \code{\link{warning}} and \code{\link{stop}} for generating warnings |
| and errors; \code{\link{conditions}} for condition handling and |
| recovery. |
| |
| \code{\link{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()) |
| } |
| \keyword{programming} |