syntax_data: {"ast_node_type":"other","tokens":[{"end":81,"kind":"keyword","start":0,"text":"(ty::GenericArgKind::Type(a_ty),"}]}
source_snippet:             (ty::GenericArgKind::Type(a_ty), ty::GenericArgKind::Type(b_ty)) => {
context_before:             }
context_after:                 Ok(relation.relate(a_ty, b_ty)?.into())