syntax_data: {"ast_node_type":"other","tokens":[{"end":75,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// provisional result is `Err(NoSolution)`. We currently treat them as
context_before:     /// A path consisting of only inductive/unproductive steps. Their initial
context_after:     /// `PathKind::Unknown` during coherence until we're fully confident in