+ JSScope* scope() const;
+ int32_t unboxedInt32() const;
+ int64_t unboxedInt52() const;
+ int64_t unboxedStrictInt52() const;
+ bool unboxedBoolean() const;
+ double unboxedDouble() const;
+ JSCell* unboxedCell() const;
+ int32_t payload() const;
+ int32_t tag() const;
+ int32_t& payload();
+ int32_t& tag();