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Avoid allocating a bool for cached computed names - #65067
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Computed name caching needs three states, but a bool pointer adds a separate allocation and another pointer for the GC to scan. Use the existing tristate representation to avoid that overhead.
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No active review issues were identified for the computed-property-name cache change.
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What changed in this PR
This PR removes a boolean allocation from the compiler’s computed-property-name cache by replacing a boolean pointer with core.Tristate.
Changes:
- Represent unknown, present, and absent cached-name states with
core.Tristate. - Update cache reads and writes to use tristate checks and conversion.
| File | Description |
|---|---|
tsc/internal/checker/types.go |
Changes the cached hasName field from *bool to core.Tristate. |
tsc/internal/checker/checker.go |
Uses tristate helpers when reading and storing computed-name results. |
Review effort: Balanced
Anders Hejlsberg (ahejlsberg)
approved these changes
Oct 30, 2026
Jake Bailey (jakebailey)
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Domain: Performance
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I found this during some unrelated work. There's no reason to allocate a bool here and use a pointer when a tristate suffices.