| dump {base} | R Documentation |
This function takes a vector of names of R objects and produces
text representations of the objects on a file or connection.
A dump file can usually be sourced into another
R (or S) session.
dump(list, file = "dumpdata.R", append = FALSE,
control = "all", envir = parent.frame(), evaluate = TRUE)
list |
character. The names of one or more R objects to be dumped. |
file |
either a character string naming a file or a
connection. "" indicates output to the console. |
append |
if TRUE, output will be appended to
file; otherwise, it will overwrite the contents of
file. |
control |
character vector indicating deparsing options.
See .deparseOpts for their description. |
envir |
the environment to search for objects. |
evaluate |
logical. Should promises be evaluated? |
If some of the objects named do not exist (in scope), they are
omitted, with a warning. If file is a file and no objects
exist then no file is created.
At present sourceing may not produce an identical copy of
dumped objects. A warning is issued if it is likely that
problems will arise, for example when dumping exotic objects such
as environments and external pointers.
dump will also warn if fewer characters were written to a file
than expected, which may indicate a full or corrupt file system.
A dump file can be sourced into another R (or
perhaps S) session, but the function save is designed to
be used for transporting R data, and will work with R objects that
dump does not handle.
To produce a more readable representation of an object, use
control = NULL. This will skip attributes, and will make other
simplifications that make source less likely to produce an
identical copy. See deparse for details.
To deparse the internal function representation rather than displaying
the saved source, use control = c("keepInteger", "quoteExpressions",
"showAttributes", "warnIncomplete"). This will lose all
formatting and comments, but may be useful in those cases where
the saved source is no longer correct.
Promises will normally only be encountered by users as a result of
lazy-loading (when the default evaluate = TRUE is essential)
and after the use of delayedAssign,
when evaluate = FALSE might be intended.
An invisible character vector containing the names of the objects which were dumped.
The envir argument was added at version 1.7.0, and changed the
default search path for named objects to include the environment from
which dump was called.
As dump is defined in the base namespace, the base
package will be searched before the global environment unless
dump is called from the top level or the envir argument
is given explicitly.
To avoid the risk of a source attribute out of sync with the actual function definition, the source attribute of a function will never be dumped as an attribute.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
dput, dget, write.
save for a more reliable way to save R objects.
x <- 1; y <- 1:10
dump(ls(patt='^[xyz]'), "xyz.Rdmped")
print(.Last.value)
unlink("xyz.Rdmped")