{"ast_node_type":"other","tokens":[{"end":98,"kind":"keyword","start":0,"text":"//!"}]}
//! row mutably in the matrix as we go along. We ignore witnesses of usefulness of the match rows.
//! [`Matrix`] stores the set of pattern-tuples under consideration. We track usefulness of each
//! We gather witnesses of the usefulness of `_` in [`WitnessMatrix`]. The algorithm that computes