error: cannot assign a value of type '?i64' to optional '?(?i64)': its payload type is '(?i64)' (note: in type position '(T)' is a single-field tuple, not a grouping — write the inner optional without parentheses)
  --> examples/diagnostics/1195-diagnostics-err-parenthesized-optional-tuple.sx:16:3
   |
16 |   outer : ?(?i64) = inner;
   |   ^^^^^^^^^^^^^^^^^^^^^^^^