packageDescription {utils} | R Documentation |
Parses and returns the ‘DESCRIPTION’ file of a package.
packageDescription(pkg, lib.loc = NULL, fields = NULL, drop = TRUE, encoding = "")
pkg |
a character string with the package name. |
lib.loc |
a character vector of directory 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. |
fields |
a character vector giving the tags of fields to return (if other fields occur in the file they are ignored). |
drop |
If TRUE and the length of fields is 1, then
a single character string with the value of the respective field is
returned instead of an object of class "packageDescription" . |
encoding |
If there is an Encoding field, to what encoding
should re-encodong be attempted? If NA , no re-encoding. The
other values are as used by iconv , so the default
"" indicates the encoding of the current locale. |
A package will not be ‘found’ unless it has a ‘DESCRIPTION’ file
which contains a valid Version
field. Different warnings are
given when no package directory is found and when there is a suitable
directory but no valid ‘DESCRIPTION’ file.
If a ‘DESCRIPTION’ file for the given package is found and can
successfully be read, packageDescription
returns an object of
class "packageDescription"
, which is a named list with the
values of the (given) fields as elements and the tags as names, unless
drop = TRUE
.
If parsing the ‘DESCRIPTION’ file was not successful, it returns
a named list of NA
s with the field tags as names if fields
is not null, and NA
otherwise.
packageDescription("stats") packageDescription("stats", fields = c("Package", "Version")) packageDescription("stats", fields = "Version") packageDescription("stats", fields = "Version", drop = FALSE)