This is a convenience wrapper for description$new().
Very often you want to read an existing DESCRIPTION
file, and to do this you can just supply the path to the file or its
directory to desc().
A command to create a description from scratch.
Currently only "!new" is implemented. If it does not start
with an exclamation mark, it will be interpreted as the file
argument.
file
Name of the DESCRIPTION file to load. If all of
cmd, file and text are NULL (the default), then the
DESCRIPTION file in the current working directory is used.
The file can also be an R package (source, or
binary), in which case the DESCRIPTION file is extracted from it, but
note that in this case $write() cannot write the file back in
the package archive.
text
A character scalar containing the full DESCRIPTION.
Character vectors are collapsed into a character scalar, with
newline as the separator.
package
If not NULL, then the name of an installed package
and the DESCRIPTION file of this package will be loaded.