reduce number of imports?

[rpruim]

Checking the package gives the following message:

> checking package dependencies ... NOTE
  Imports includes 21 non-default packages.
  Importing from so many packages makes the package vulnerable to any of
  them becoming unavailable.  Move as many as possible to Suggests and
  use conditionally.

If we can reduce the dependency tree, that is probably good for any number of reasons.

[nicholasjhorton]

I concur.

Is this just the "Imports" list (20 at present based on my count for the 1.8.3 version on CRAN)?

[rpruim]

Just imports. I added {purrr} earlier today to hit 21. But I may be removing {purrr} in favor of a different solution to #779

[rpruim]

I'm going through the imports to find packages used only in isolated corners of mosaic. For those, I'll likely use rlang::check_installed() before any uses of the package. That will prompt the user to install the package if it is not and quit execution if they choose not to install.