Preallocate types slice in getLiteralTypeFromProperties #2458
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Pull request overview
This PR optimizes the getLiteralTypeFromProperties function by preallocating the types slice with an appropriate capacity to avoid dynamic growth during append operations.
Key changes:
- Stores
propsandindexInfosin variables before the loops to calculate capacity - Preallocates the
typesslice with capacitylen(props) + len(indexInfos) - Maintains identical behavior while improving performance by reducing allocations
ahejlsberg
approved these changes
Jan 9, 2026
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For #2454