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HyperScript engine does not work properly with For

Open grimalschi opened this issue 9 months ago • 3 comments

Describe the bug

Function "For" in HyperScript mode loses connection with signals when list changes.

Your Example Website or App

https://playground.solidjs.com/anonymous/2103f083-762b-40be-b23f-114309a0142f

Steps to Reproduce the Bug or Issue

  1. Click "add"
  2. Click "demo"

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Expected behavior

Here is correct behavior using TSX: https://playground.solidjs.com/anonymous/9392c73a-cd81-4260-9f23-508104380960

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Screenshots or Videos

No response

Platform

  • OS: macOS
  • Browser: Vivaldi
  • Version: 7.0.3495.29

Additional context

I have also checked html`` function, it works as expected (https://playground.solidjs.com/anonymous/5e9b68a0-5d8f-4f30-8ec3-d4c8fb24f766).

The closest solution is to wrap children in function (https://playground.solidjs.com/anonymous/32865f62-3ba6-45f3-a0a1-e8bc9adced6a), but in this case Solid redraws all children everytime I add new element in array, which is undesired behavior.

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grimalschi avatar Mar 21 '25 04:03 grimalschi

Thanks yeah I can reproduce. I made some pretty heavy changes to HyperScript a couple years ago to handle Context + Fragments and while it worked then, over time we have been optimizing away unnecessary wrappers in Solid core and it turns out HyperScript is the only renderer that needs them. I want to re-evaluate this solution on a whole because basically the reactivity leaks upwards here in a way that is more or less prevented by our JSX compiler and html function.

The gist of it is that we defer evaluation here and it leads to render effects being created in the parent context instead of inside the For which means when the parent insert re-runs it inadvertently releases the render effects on the other divs. Given my current understanding of how these things should work this is all wrong.

ryansolid avatar Mar 27 '25 00:03 ryansolid

https://playground.solidjs.com/anonymous/0392c578-9678-474a-b500-e2d31f64ad70

but this over renders

mizulu avatar May 01 '25 16:05 mizulu

For references there are a bunch of messages and a thread about this in https://discord.com/channels/722131463138705510/780502110772658196/1367529419052285982 https://discord.gg/solidjs invite if you need

titoBouzout avatar May 01 '25 20:05 titoBouzout