R: Package Description

packageDescription {utils}

R Documentation

Package Description

Description

Parses and returns the ‘DESCRIPTION’ file of a package.

Usage

packageDescription(pkg, lib.loc = NULL, fields = NULL, drop = TRUE,
                   encoding = "")

Arguments

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, what re-encoding should be attempted? If NA, no re-encoding.

Details

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.

Value

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 NAs with the field tags as names if fields is not null, and NA otherwise.

Examples

packageDescription("stats")
packageDescription("stats", fields = c("Package", "Version"))

packageDescription("stats", fields = "Version")
packageDescription("stats", fields = "Version", drop = FALSE)

[Package utils version 2.1.1 ]