Example use case (not resource management; convenient via iterable weak set)

[tc39]

Example use case (not resource management; convenient via iterable weak set)

[dtribble]

This is a great use. Thanks. Can you post a pointer to the code so that we can try enhancing it with weak ref code? I will be interested in trying the proposed weakref approach and trying it with various weak collection options.

Also, is there anything in the standard or other source of desire/requirement for making a similar cleanup step if the node is just dropped on the floor (e.g., some incidental additional value in triggering the cleanup).

[titzer]

+1 to "iterable weak set", as another use case I have heard is implementing the "become" operator in languages like Smalltalk.

Is it possible to change the title of an issue? If so, I suggest adding "iterable weak set" to the title here.

[axkibe]

I got a rather simple other usecase, I've objects representing points in a 2d plane, I like to freeze them and I would like to intern them, so a simple a === b would test them for equality. For this I'd put all the points generated in a weak table with some kind of hash value to test if this object already exists before creating a new one. Similar for objects representing lines or other geometric objects.

[domenic]

@dtribble the code is in roughly these locations:

• https://github.com/jsdom/jsdom/blob/a0b7f8a77789fbc4467031a19865a2d1aef27796/lib/jsdom/living/nodes/Document-impl.js#L740-L750
• https://github.com/jsdom/jsdom/blob/a0b7f8a77789fbc4467031a19865a2d1aef27796/lib/jsdom/living/nodes/Document-impl.js#L624-L628
• https://github.com/jsdom/jsdom/blob/a0b7f8a77789fbc4467031a19865a2d1aef27796/lib/jsdom/living/nodes/Node-impl.js#L313-L315
• https://github.com/jsdom/jsdom/blob/a0b7f8a77789fbc4467031a19865a2d1aef27796/lib/jsdom/living/traversal/NodeIterator-impl.js#L78-L84

I'm not sure which node you'd be referring to in "is there anything in the standard or other source of desire/requirement for making a similar cleanup step if the node is just dropped on the floor", but I don't think there is any such desire/requirement.

@titzer I'm not sure why we'd call out the iterable weak set API shape specifically here; this could be accomplished with any API shape, from the proposal's weak ref, to an iterable weak map, to an iterable weak set, ...

[titzer]

@domenic I simply meant using "iterable weak set" in a conceptual sense to summarize the use case described here, not any particular API commitment.

[domenic]

Ah OK, sure, I'll do that if you think that there's a tie between a generalization of this use case and the API shape.

[littledan]

@mathiasbynens wrote up something related to this use case in the explainer. Is there anything else to add, or is it OK to close this issue?

[littledan]

Closing due to #17 (comment)