| r -- sk ∈ st, is_referencevalue(st[r -- sk]) ∧ validrefnotnull(str, st[r -- sk] .refval, ty, st), r ∈ st ⊦ st[r -- sk] .refval ∈ st |
r ∈ st, validrefnotnull(str, st[r -- sk] .refval, ty, st), is_referencevalue(st[r -- sk]), r -- sk ∈ st ⊦ st[r -- sk] .refval ∈ st
[[CONCRETESIMPRULES : ()]]