pkgDesc: Version of packageDescription() as Simple Vector

In sfsmisc: Utilities from 'Seminar fuer Statistik' ETH Zurich

Version of packageDescription() as Simple Vector

Description

a simple “version”, or wrapper for packageDescription(), returning a named character vector, including "file", and still has a useful print() method.

Usage

pkgDesc (pkg, lib.loc = NULL, fields = NULL, onlyLT = 99, ...)
pkgBuilt(pkg, lib.loc = NULL, ...)

Arguments

pkg	a character string, name of an installed R package.
lib.loc	library location to find the package in; the default NULL uses the full .libPaths().
fields	a character vector (or NULL) specifying fields to be returned.
onlyLT	positive integer specifying an upper limit on the number of characters of fields to be returned and printed.
...	further optional arguments passed to packageDescription().

Value

a named character vector, with names, the fields, identical to the names of the list returned by packageDescription, plus its "file" attribute. Additionally the resulting vector is of class "Dlist" which activates a useful print() method.

Note

The file is always returned; not the least that the author wants to see it quite often as his .libPaths() is non-trivial and typically longer than 4 entries.

I started to hate screen fulls of Authors and/or Description; when I wanted quite basic info, hence onlyLT with a reasonable default.

Author(s)

Martin Maechler, Jan. 2021

See Also

packageDescription, .libPaths.

Examples

str(pd <- pkgDesc("sfsmisc"))
pd[c("Date","Packaged", "Built","file")]

## see the effects of  `onlyLT` :
str(p1 <- pkgDesc("sfsmisc", onlyLT = Inf)) # .. [1:25] ..
str(pD  <-pkgDesc("sfsmisc"              )) # .. [1:21] ..
str(p50 <-pkgDesc("sfsmisc", onlyLT = 50 )) # .. [1:18] ..
t(sapply(list(full = p1, def. = pD, p50 = p50),
         function(pd) {n <- nchar(pd); c(summary(n)[-1], SUM = sum(n))}))

pkgBuilt("sfsmisc")

## Show "Built" (and "file") for all packages whose namespaces are loaded:
lNs <- loadedNamespaces()
mlNs <- sapply(lNs, pkgBuilt)
t(mlNs) # typically prints nicely

pkgs <- c("grid", "lattice", "MASS", "Matrix", "nlme", "lme4", "sfsmisc")
pkgs <- c("foobar", "barbar", pkgs, "kitty") # + names that typically don't exist
pkgsOk <- basename(find.package(pkgs, quiet=TRUE))
mpkg <- sapply(pkgsOk, pkgBuilt)
stopifnot(is.matrix(mpkg), nrow(mpkg) == 2)
mpkg["Built",]

sfsmisc documentation built on Nov. 21, 2025, 9:06 a.m.