start section on substitution RHS restrictions
start section on substitution RHS restrictions

More specifics need to be added.
MasterDuke17/doc,tbrowder/doc,perl6/doc,MasterDuke17/doc,tbrowder/doc,perl6/doc,perl6/doc,MasterDuke17/doc,perl6/doc,tbrowder/doc,MasterDuke17/doc,perl6/doc,tbrowder/doc