- as "$hashref->{key}[$idx]{$field} = $value". An exception is thrown
- if vivification is needed to store the value, which means that
+ as "$hashref->{key}[$idx]{$field} = $value" or "for
+ ($hashref->{key}[$idx]{$field}) { ... }". An exception is thrown if
+ vivification is needed to store the value, which means that