With every new release I go through all the "What's new for this release" section of IBM's KnowledgeCenter. For IBM i 7.4 and the CL programming language there is only one addition this release: %PARMS built in function. It appears to be identical to the %PARMS built in function in RPG. It is the way to determine how many parameters have been passed to a program or procedure, and from that stop the program from erroring if too few parameters are passed.
In the past I wrote about coping with to few parameters being passed to a CL program, but the new BiF is a lot neater and easier for someone else to understand.
As I said above %PARMS is available in RPG: