Handle the "do nothing" case for checking inputs
Handle the "do nothing" case for checking inputs

Kitware/sprokit,linus-sherrill/sprokit,mathstuf/sprokit,linus-sherrill/sprokit,Kitware/sprokit,mathstuf/sprokit,linus-sherrill/sprokit,Kitware/sprokit,linus-sherrill/sprokit,Kitware/sprokit,mathstuf/sprokit,mathstuf/sprokit