| (_,Ast.Exp(e2)) -> subexp (unify_expression e2) re1
| (Ast.TopExp(e1),Ast.TopExp(e2)) -> unify_expression e1 e2
+ | (Ast.TopInit(i1),Ast.TopInit(i2)) -> unify_initialiser i1 i2
(* can match a rule_elem in different parts *)
| (Ast.Ty(t1),Ast.Ty(t2)) -> return true