syntax_data: {"ast_node_type":"other","tokens":[{"end":57,"kind":"keyword","start":0,"text":"ty::GenericArgKind::Type(ty)"}]}
source_snippet:         ty::GenericArgKind::Type(ty) => match ty.kind() {
context_before:     let maybe_unsizing_param_idx = |arg: ty::GenericArg<'tcx>| match arg.kind() {
context_after:             ty::Param(p) => Some(p.index),