myStartupUtilities {startupmsg}

Example functions to utilities for start-up messages

Description

Illustration of package 'startupmsg'

Usage

mySMHandler(c)
mystartupMessage(..., domain = NULL, pkg = "", type="version", 
                 SMHandler=mySMHandler, endline = FALSE)

buildStartupMessage(..., pkg, library=NULL, domain=NULL, 
                    packageHelp=FALSE, MANUAL = NULL, VIGNETTE = NULL,
                    SMHandler=mySMHandler)

Arguments

c

an object of class StartupMessage

pkg

a character string with the name of a single package

library

a character vector with path names of R libraries, or NULL. The default value of NULL corresponds to all libraries currently known. If the default is used, the loaded packages are searched before the libraries

domain

see gettext. If NA, messages will not be translated.

type

character – the type part of an S3-object of class StartupMessage; currently, type should be in c("version","notabene","information").

SMHandler

function to handle the output of an object of class StartupMessage, defaults to mySMHandler; btw: SMHandler stands for /S/tartup/M/essage/Handler/

endline

logical: shall there be an empty line (TRUE) or a line with linestarter in the end?

packageHelp

logical: is there help available as ?<pkg-name> ?

MANUAL

character or NULL if !is.null(MANUAL) the name of a manual distributed together with the package (with relative path within the library) or an URL

VIGNETTE

character or NULL if !is.null(VIGNETTE) an indication of one or more vignettes available to this package

...

character vectors (which are pasted together with no separator)

Details

mystartupMessage redirects the output of startupMessage to have a particular output function SMHandler issue the message; to see how such a function may be defined, have a look at code of the default function mySMHandler:

mySMHandler <- function(c) {
    pkg <- startupPackage(c) # get the package slot of c
    #prefix a starter for each new line of the message:
    linestarterN <- paste(":",pkg,"> ", sep ="")                              
    linestarterN <- paste("\n",linestarter, sep ="")
    linestarterE <- paste(linestarterN,"$",sep="")
    writeLines(paste(linestarter, sub(linestarterE,"\n", 
               gsub("\n",linestarterN,conditionMessage(c))),
                    sep=""),stderr())}

Just like for startupMessage, for mystartupMessage, too, restarts muffleMessage(), onlytypeMessage(c0,atypes), custom(c,f) are available (confer startupmsg).

To generate a complete start-up message, we provide buildStartupMessage: this function automatically generates

• a start-up message of condition StartupMessage with type "version" as to the version information.

• additional messages of class StartupMessage and of type "notabene" according to the ... argument

• a message of class StartupMessage and of type "information" mentioning
  

  • ?"}<pkg-name>\code{" – according to argument packageHelp,

  • NEWS("}<pkg-name>\code{"), if there is a ‘NEWS’ file,

  • URL, if there is a URL mentioned in the ‘DESCRIPTION’ file,

  • if there is a MANUAL argument, the file / the URL to this manual

  • if there is a VIGNETTE argument, VIGNETTE is printed out indicating a vignette location

The user may suppress the start-up messages produced by buildStartupMessages in two ways: Either by suppressStartupMessages(expr) and onlyversionStartupMessages(expr, atypes="version") as for startupmessage (confer startupmsg), or – as proposed by Brian Ripley – by options; let us describe the latter possibility here:

• options("StartupBanner"="off") switches off all start-up messages

• if option "StartupBanner" is not defined (default) or setting options("StartupBanner"=NULL) or options("StartupBanner"="complete") the complete start-up banner is displayed

• for any other value of option "StartupBanner" (i.e., not in c(NULL,"off","complete")) only the version information is displayed

Author(s)

Peter Ruckdeschel [e-mail]

See Also

Mail "[Rd] Wishlist: 'quietly' argument for .onAttach() / .First.lib() " on r-devel by Brian Ripley, https://stat.ethz.ch/pipermail/r-devel/2006-April/037281.html

Examples

## a set of test messages

msg <- "Note that you may set global options by options() --- cf. ?\"options\"."

## issuing of messages controlled by options()
buildStartupMessage(pkg="stats", msg) 
suppressStartupMessages(buildStartupMessage(pkg="stats", msg) )
suppressMessages(buildStartupMessage(pkg="stats", msg))
onlytypeStartupMessages(buildStartupMessage(pkg="stats", msg),
          atypes="version")

getOption("StartupBanner")
buildStartupMessage(pkg="stats", msg)

options("StartupBanner"="off");getOption("StartupBanner")
buildStartupMessage(pkg="stats", msg)

options("StartupBanner"="complete");getOption("StartupBanner")
buildStartupMessage(pkg="stats", msg)

options("StartupBanner"="something else");getOption("StartupBanner")
buildStartupMessage(pkg="stats", msg)

options("StartupBanner"=NULL);getOption("StartupBanner")
buildStartupMessage(pkg="stats", msg)


MNH <- "https://www.r-project.org/"
buildStartupMessage(pkg="stats", msg, packageHelp=TRUE, MANUAL=MNH)
## not quite a manual, but to illustrate the principle:
## "demo/nlm.R" as a "manual": to be system-independent the 
## first call is to be preferred 
buildStartupMessage(pkg="stats", msg, packageHelp=TRUE, MANUAL=c("demo","nlm.R"))
###  works, too, (i.e. is equivalent) under Linux and Windows (at least):
buildStartupMessage(pkg="stats", msg, packageHelp=TRUE, MANUAL="demo/nlm.R")