syntax_data: {"ast_node_type":"other","tokens":[{"end":59,"kind":"keyword","start":0,"text":"@variant(mir_unwind_terminate_reason,"}]}
source_snippet:             @variant(mir_unwind_terminate_reason, Abi) => {
context_before:         parse_by_kind!(self, expr_id, _, "unwind terminate reason",
context_after:                 Ok(UnwindTerminateReason::Abi)