| 22:15 | <shu> | we might've accidentally made template literal arrays eternal again? |
| 22:16 | <shu> | we (chrome) recently discovered the note for [[TemplateMap]] in https://tc39.es/ecma262/#table-realm-record-fields is not true, because, well, WeakMaps and WeakRefs exist |
| 22:44 | <Ashley Claymore> | It seems to just not be true in general. The array could still be reachable by anything live having a reference to it. The array can be passed around. Unless it means the literal accessing of the [[array]] field rather than the value? |
| 22:45 | <shu> | good point, i think that note is probably in general wrong |
| 22:46 | <shu> | but the original intention was assuming no live strong references to the template array, we could collect it if the parse node was no longer reachable |
| 22:47 | <Ashley Claymore> | That seems OK? Even if the array is in a WeakRef. Or is there a risk to making that collection observable? |
| 22:48 | <shu> | but it is not in fact unobservable to collect them, because of weakrefs |
| 22:48 | <shu> | i think we should clarify that note because it's saying a collecting implementation strategy is allowed because of unobservability, which is false |
| 22:49 | <shu> | maybe we don't need to say anything more than "it's observable in weak collections and weakrefs and that's fine" |
| 22:50 | <shu> | it's also not very clear to me what a Parse Node becoming unreachable means |
| 22:51 | <shu> | now that we talk about liveness for other things in the spec, we should give these the same treatment |
| 22:51 | <Ashley Claymore> | When can parse nodes be collected? Eval and script tags? |
| 22:51 | <shu> | beats me! |
| 22:51 | <shu> | they're technically spec fiction |
| 22:51 | <shu> | oh no, maybe not, because functions hold on to them? |
| 23:05 | <bakkot> | yeah, functions hold on to them |
| 23:05 | <bakkot> | and that's how you'd normally re-manifest it: () => tag`foo` or whatever |
| 23:10 | <shu> | but the only way we would collect them is if the toplevel Script or Module that has the root Parse Node itself becomes unreachable at some point |
| 23:10 | <shu> | and that i guess is currently up to the host |
| 23:41 | <bakkot> | the Script is not reachable from code, from the POV of the spec |
| 23:41 | <bakkot> | like if you just have tag`foo` in your program, not in a closure, then after the main body of the script runs you can collect the array for that template |
| 23:41 | <bakkot> | (ignoring WeakRefs, and assuming tag doesn't create a longer-lived reference) |
| 23:43 | <shu> | isn't the entry point to parse a script from the host though? |
| 23:45 | <shu> | anyway that part isn't so important |
| 23:46 | <shu> | we should say that the liveness of the template array literal is tied to the liveness of the Parse Node, which may be observed by weak collections and weak refs |