perf: empty array

[TwoFX]

No description provided.

[TwoFX]

!radar

[leanprover-radar]

Benchmark results for 1c51097 against 67526ae are in. No significant results found. @TwoFX

• ✅ build//instructions: -3.7G (-0.03%)

Medium changes (1✅)

• ✅ compiled/parser//instructions: -105.6M (-0.30%)

[mathlib-lean-pr-testing]

Mathlib CI status (docs):

• ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the nightly-with-mathlib branch. Try git rebase 67526ae54d733251644d5cebb9fa5a77318fecc4 --onto c632a0a0e434a951cdcf61bb4da3344abadd5587. You can force Mathlib CI using the force-mathlib-ci label. (2026-09-04 11:09:28)

[leanprover-bot]

Reference manual CI status:

• ❗ Reference manual CI will not be attempted unless your PR branches off the nightly-with-manual branch. Try git rebase 67526ae54d733251644d5cebb9fa5a77318fecc4 --onto 58774429865502f05c63239266aac30ef1e91ef7. You can force reference manual CI using the force-manual-ci label. (2026-09-04 11:09:30)