syntax_data: {"ast_node_type":"variable","tokens":[{"end":61,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let full_yield_ty = body.yield_ty().unwrap();
context_before:                 // For AsyncGen we need `yield Poll<OptRet>::Pending`
context_after:                 let ty::Adt(_poll_adt, args) = *full_yield_ty.kind() else { bug!() };