Where a city/state field lives. A union of two shapes, discriminated on whether the spec carries its own city sub-selector: combined (a single selector whose text is "City, ST" — a plain TextFieldSpec) or nested (per-row city/state sub-selectors — a NestedCityStateSpec).
Where a city/state field lives. A union of two shapes, discriminated on whether the spec carries its own
citysub-selector: combined (a singleselectorwhose text is "City, ST" — a plain TextFieldSpec) or nested (per-rowcity/statesub-selectors — a NestedCityStateSpec).