syntax_data: {"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"CoroutineKind::Desugared(CoroutineDesugaring::Gen,"}]}
source_snippet:             CoroutineKind::Desugared(CoroutineDesugaring::Gen, _) => {
context_before:             }
context_after:                 // Compute Option<yield_ty>