]> domain axiom define function predicate method field true false null goto label if elseif else while result old acc none write epsilon wildcard perm unfolding folding applying packaging forperm constraining let in var fresh forall exists unique returns requires ensures invariant assert assume inhale exhale fold unfold wand package apply == != ==> <==> || && < > <= >= + - * / \\ \% \/ --* union intersection setminus ++ in subset ! :: Int Bool Rational Perm Ref Seq Set Multiset