JuliaLang / julia / 475

78%

Build Type

push

buildkite

Committed by web-flow

Commit Message

reduce: avoid spurious widening for array reduction with `init` (#62993)

This is a noticeable improvement to nested reductions in the presence of
arrays.

It is a bit silly to have to work around the recursion heuristic in this
way, but I am not sure we can do much better unless we teach it to
associate an argument's type with the dispatch that is keyed on it
(these `mapreduce` methods are non-recursive since they immediately
invoke different Methods, but the compiler has a very hard time seeing
that from the types alone).

This makes many pithy reduce-heavy examples like `maximum(count(!iszero,
v .* i) for i in 1:3)` fully infer and `--trim`-compatible.

Prepared with assistance from Claude Fable 5 🤖

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

Coverage Stats

8 of 8 new or added lines in 1 file covered. (100.0%)

225 existing lines in 8 files now uncovered.

69475 of 88707 relevant lines covered (78.32%)

23443635.72 hits per line