Note this clarification text has been added to the spec regarding interpretation of variable bindings for record, list, and other complex specification types:
Algorithm steps may declare named aliases for any value using the form “Let x be someValue”. These aliases are reference-like in that both x and someValue refer to the same underlying data and modifications to either are visible to both. Algorithm steps that want to avoid this reference-like behavior should explicitly make a copy of the right-hand side: “Let x be a copy of someValue” creates a shallow copy of someValue.
This was added in response to my clarification request in tc39/ecma262#752 noting that my interpretation of the behaviour of CompletePropertyDescriptor and its usage in [[GetOwnProperty]] for Proxy objects.
I imagine that to guarantee correctness and closeness to the spec in the future, we're going to need to adjust jsexplain's heap structure to match this.
Note this clarification text has been added to the spec regarding interpretation of variable bindings for record, list, and other complex specification types:
This was added in response to my clarification request in tc39/ecma262#752 noting that my interpretation of the behaviour of
CompletePropertyDescriptorand its usage in[[GetOwnProperty]]for Proxy objects.I imagine that to guarantee correctness and closeness to the spec in the future, we're going to need to adjust jsexplain's heap structure to match this.