syntax_data: {"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"ty::UpvarCapture::ByRef(kind)"}]}
source_snippet:                 ty::UpvarCapture::ByRef(kind) => Ty::new_ref(
context_before:                 ty::UpvarCapture::ByValue | ty::UpvarCapture::ByUse => parent_capture_ty,
context_after:                     tcx,