JavaScript serialization semantics

	A	B	C	D	E	F	G	H
1		Q (default semantics)	Q.passByCopy	JSON.stringify	Structured Clone	Proposed default	Proposed.passByCopy	Proposed pass by construction
2	Object	pass-by-promise?	shallow copy	deep copy (own non-function data props only, non-cyclic)	deep copy (own data props only, cyclic)	pass-by-reference	shallow copy	by construction
3	Function	pass-by-proxy	?	error	error	pass-by-reference	shallow copy if closed; else error	by construction
4	Array	shallow copy?	shallow copy?	deep copy	deep copy	pass-by-reference	shallow copy	by construction
5	Number	copy	copy	copy	copy	copy	copy	N/A
6	String	copy	copy	copy	copy	copy	copy	N/A
7	Boolean	copy	copy	copy	copy	copy	copy	N/A
8	null	copy	copy	copy	copy	copy	copy	N/A
9	undefined	copy	copy	error	copy	copy	copy
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13	Deep copy = recursively copies the parts using the same pass-by-copy semantics (i.e. the copied object is guaranteed not to contain any more references to remote data)
14	Shallow copy = recursively copies the parts using the default semantics (i.e. the copied object may still contain references to remote data)
15	pass-by-promise = the receiving side receives a remote promise object
16	pass-by-proxy = the receiving side receives a function that calls the original and returns a promise for the result
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