{"ast_node_type":"other","tokens":[{"end":100,"kind":"keyword","start":0,"text":"///"}]}
/// the depth of patterns, whereas `compute_exhaustiveness_and_usefulness` is worst-case exponential
/// algorithm in [`crate::usefulness`], this does a different traversal. Notably this is linear in
/// (exhaustiveness is NP-complete). The core difference is that we treat sub-columns separately.