The parameter was none_cats: &[String] and the body consulted it exactly once,
for emptiness -- a boolean wearing a list's type, since the aggregation runs
over key.0 through matching_values. git log -S back to the commit that
introduced Axis::None shows it never examined an element, so the name promised a
filter the function has never performed.
Aggregation::{Exact, OverHidden} admits only the two states the body
distinguishes, and Aggregation::of reduces the list once at the boundary that
holds it. The regression guard is the signature: two lists with the same
emptiness and different contents is no longer a constructible call.
recompute_formulas and aggregate_raw keep &[String] -- they walk the elements.
improvise-5jm5
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FC2jVn8Au7E9JPkw6bwXXH
Edward Langley
3f8f7cb765