syntax_data: {"ast_node_type":"other","tokens":[{"end":48,"kind":"keyword","start":0,"text":"teach:"}]}
source_snippet:     teach: bool = (false, parse_bool, [TRACKED],
context_before:     #[rustc_lint_opt_deny_field_access("use `Session::teach` instead of this field")]
context_after:         "show extended diagnostic help (default: no)"),