DMN17 — Spec does not mandate that all user-defined function parameters are utilised

Section "10.3.2.13.2 User-defined functions" provides definition and invocation semantics for user defined functions but permits unused parameters.

As DMN is to be 'executable documentation' I suggest that unused parameters provide documentation that does not reflect reality.

I propose the follow additional paragraph to "10.3.2.13.2 User-defined functions" :

"The body expression of a user-defined function SHALL utilise every formal parameter. "