| st[r -- fs '] = refval(r0), maxpath(str, r, st) = 1, 1 ≤ maxpath(str, r0, st), validrefs(str, r ', st[r -- _type] .type, st), fs ' ∈ instfields(st[r -- _type] .type .class), is_obj(str, r, st) ⊦ validrefset(str, r, st) = ∅, # validrefset(str, r, st) = 0, maxpath(str, r0, st) = 0, junkref(str, r, st), cyclic(str, r, st), has_reffield(r, st) |
⊦ is_obj(r, st) → (has_reffield(r, st) ↔ (∃ fs. fs ' ∈ instfields(st[r -- _type] .type .class) ∧ is_reftype(fs .type)))
is_obj(r, st), st[r -- fs '] = refval(r0), maxpath(str, r, st) = 1, 1 ≤ maxpath(str, r0, st), validrefs(str, r ', st[r -- _type] .type, st), fs ' ∈ instfields(st[r -- _type] .type .class), is_obj(str, r, st) ⊦ validrefset(str, r, st) = ∅, # validrefset(str, r, st) = 0, maxpath(str, r0, st) = 0, junkref(str, r, st), cyclic(str, r, st), ∃ fs. fs ' ∈ instfields(st[r -- _type] .type .class) ∧ is_reftype(fs .type)
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ ¬ is_obj(r, st) → ¬ is_obj(str, r, st)])], [EXTRATERMS : (st, r)]]