tree 7c27914bb605349ff362708bdff06a18cce758c0
parent 5770f51a37b8b76255b68ec5b3d471614ee9752c
author Patrick Williams <patrick@stwcx.xyz> 1642525184 -0600
committer Patrick Williams <patrick@stwcx.xyz> 1642525268 -0600

util: variant: add static assert

The two variant utilities both have an 'Unused' template parameter pack
which is expected to be empty.  Add static assert to confirm the
parameter pack is indeed always empty.  (Generally the non-empty
parameter pack should match with a specialization.)

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Iae4523142df563d208e20ab81dd47266b3f7dd27