| `Level (child_prec, child_assoc) ->
let t' = aux xmlattrs mathonly xref pos child_prec uris t in
add_parens child_prec child_assoc pos prec t'
| `Level (child_prec, child_assoc) ->
let t' = aux xmlattrs mathonly xref pos child_prec uris t in
add_parens child_prec child_assoc pos prec t'