Message-ID: <CAPPM_gSe+nGTxi2qZcM4DKW5=_SeO+z80vWb5fEkMp+iQMV5Tw@mail.gmail.com>
Date: 2017-12-06T12:45:29Z
From: Joshua Ulrich
Subject: [R-pkg-devel] Conditionally register method with generic in other package
I have a feeling I know the answer to this question, but I'm asking
with the hope that I learn something new.
Package A defines a S3 generic function, "foo()". Package B defines a
S3 class "bar", and a foo.bar() method. This method is not strictly
necessary for the package to function, and package A has many
dependencies.
To avoid excessive dependencies, I would like to only register
foo.bar() if package A is installed at the time package B is
installed. If package A is installed after package B, then warn the
user when package B is loaded and/or attached, so they can re-install
A and have foo.bar() registered correctly.
I could figure out a way to do this manually, but doubt it would be
CRAN-approved. What is the recommended way to handle this situation?
I've received one suggestion to split B into 2 packages: one without
the method, and one with. Are there other alternatives?
Thanks,
Josh
--
Joshua Ulrich | about.me/joshuaulrich
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