syntax_data: {"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"translate_lang:"}]}
source_snippet:     translate_lang: Option<LanguageIdentifier> = (None, parse_opt_langid, [TRACKED],
context_before:         "emit directionality isolation markers in translated diagnostics"),
context_after:         "language identifier for diagnostic output"),