syntax_data: {"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"hint_mostly_unused:"}]}
source_snippet:     hint_mostly_unused: bool = (false, parse_bool, [TRACKED],
context_before:         "allow deducing higher-ranked outlives assumptions from coroutines when proving auto traits"),
context_after:         "hint that most of this crate will go unused, to minimize work for uncalled functions"),