StartupUtilities | R Documentation |
several utilities to produce start-up messages
readVersionInformation(pkg, library=NULL)
readURLInformation(pkg, library=NULL)
pointertoNEWS(pkg, library=NULL)
infoShow(pkg, filename, library=NULL)
NEWS(pkg, library=NULL)
TOBEDONE(pkg, library=NULL)
StartupMessage(message, call = NULL, pkg="",
type="version", endline = FALSE)
startupPackage(startupmessage)
startupType(startupmessage)
startupEndline(startupmessage)
startupMessage(..., domain = NULL, pkg = "",
type="version", endline = FALSE)
suppressStartupMessages(expr)
onlytypeStartupMessages(expr,atypes="version")
pkg |
a character string with the name of a single package |
library |
a character vector with path names of R libraries, or |
filename |
name of the file which is to be displayed by |
message |
a character string – the message part of an S3-object of class |
call |
a call expression – the call part of an S3-object of class |
type |
character – the type part of an S3-object of class |
endline |
a logical – the decision on the ending of an S3-object of class |
startupmessage |
the |
domain |
see |
atypes |
a vector of characters – the types of |
expr |
expression to evaluate. |
... |
character vectors (which are pasted together with no separator) |
readVersionInformation
and readURLInformation
read the ‘DESCRIPTION’ file of the package.
readVersionInformation
returns a list with elements ver
and title
for the version and title
to be found in the ‘DESCRIPTION’ file; if there is a URL
entry it is returned by readURLInformation
else readURLInformation
returns NULL
.
If there is a ‘NEWS’ in the package main folder, pointertoNEWS
returns a string with an expression how
to retrieve this file from within R, else pointertoNEWS
returns NULL
.
infoShow
displays the file filename
in the package main folder using file.show
– if it exists;
NEWS
in particular displays the ‘NEWS’ file,
and analogously, TOBEDONE
in particular displays the ‘TOBEDONE’
file; takes up an idea by Andy Liaw.
A new sub-condition StartupMessage
to message
is introduced,
with a constructor with the same name.
In addition to the slots of message
, it also has slots package
(for the package they are for),
type
(currently in c("version","notabene","information")
), and
endline
(a logical).
These slots may be accessed by startupPackage
, startupType
, and
startupEndline
, respectively.
startupMessage
issues a start-up message which also is represented as a condition.
While the start-up message is being processed, the following restarts are available:
muffleMessage()
to suppress the StartupMessage
,
onlytypeMessage(c0,atypes)
to filter out types not mentioned in atypes
of StartupMessages
-argument c0
,
custom(c,f)
to apply the user-defined function f
to StartupMessages
-argument c0
instead of the usual procedure
The user may suppress the start-up messages produced by these utilities as follows:
suppressStartupMessages(expr)
suppresses all messages issued by startupMessage
in the expression expr
within the parentheses
suppressPackageStartupMessages(expr)
:
from package version 0.5 on, is the same as suppressStartupMessages
for our start-up banners, but more
generally suppresses all messages of S3-class packageStartupMessage
(from base package)
onlyversionStartupMessages(expr, atypes="version")
only shows messages issued by startupMessage
in the expression expr
within the parentheses, if
there slot type
is contained in the atypes
argument
by the custom
restart (see example by Seth Falcon)
Thanks to Seth Falcon for his helpful comments.
Peter Ruckdeschel peter.ruckdeschel@uni-oldenburg.de
buildStartupMessage
for some illustration;
for the ideas taken up in this package, see mails "[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,
by Andy Liaw,
https://stat.ethz.ch/pipermail/r-devel/2006-April/037286.html,
by Seth Falcon,
https://stat.ethz.ch/pipermail/r-devel/2006-April/037317.html,
and again by Seth Falcon,
https://stat.ethz.ch/pipermail/r-devel/2006-April/037367.html,
and by the author,
https://stat.ethz.ch/pipermail/r-devel/2006-April/037382.html
## a set of test messages
several.messages<-function() {
startupMessage("this is a type 'version' startup message", pkg="PKG")
startupMessage("this is a type 'information' startup message",
pkg="PKG", type="information")
message("this is an ordinary message")}
## issuing of messages with different wrappers
several.messages()
suppressStartupMessages(several.messages())
suppressMessages(several.messages())
onlytypeStartupMessages(several.messages(),atypes=c("version","notabene"))
##Example by Seth Falcon:
## Here is a test function
doit <- function() {
several.messages()
return(123)
}
## Here is an example message handler. Here, you could write messages
## to a file, send them as email to your friends or enemies, etc.
## For the example, we'll just prepend 'MSG:'
msgLogger <- function(m) {
types<-paste("(", startupType(m),"):", sep="")
cat(paste("MSG: ",types, conditionMessage(m)), "\n")
}
## Finally, call the doit function and customize how messages are
## handled.
withCallingHandlers(doit(),
StartupMessage=function(m) {
invokeRestart("custom", m, msgLogger)
})
### reading information file utilities
readVersionInformation("stats")
readURLInformation("stats")
## for packages with URL file see e.g. dse1
pointertoNEWS("stats") ## no NEWS file;
## IGNORE_RDIFF_BEGIN
NEWS("stats") ## no NEWS file;
## for packages with NEWS file see e.g. randomForest, distr
## IGNORE_RDIFF_END
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