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[compiler] Refine Object.fromEntries mutation effects - #38192
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Object.fromEntries reads its iterable and captures entry values into the returned object. Modeling it as conditionally mutating the iterable merged the argument, result, and consumers into one reactive scope. Use Capture with a Create/Capture aliasing signature in both compilers so these values can have independent reactive scopes. Fixes react#34232 Co-authored-by: lauren <lauren@anysphere.co>
Object.fromEntries can consume its iterator and invoke object-key conversion. Treating every input as capture can cache mutated state across renders. Keep conditional transitive mutation in the default signature. Refine it to capture for local entries arrays whose primitive keys and alias uses prove that evaluation cannot mutate them.
magic-akari
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November 10, 2026 18:21
willbyers1
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Nov 10, 2026
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Conservative mutation effects for
Object.fromEntriesmerge safe local entry arrays, their results, and downstream consumers into one reactive scope.Refine both compilers to use capture effects for local entry arrays proven to have primitive keys and no potentially mutating uses. Preserve conditional mutation effects for other inputs so iterator consumption and key conversion remain correct across renders.