Const
An Explode Array (PLAN ยง11.20): its column, its path of keys and its new column's name, always written, exactly as held ('' and empty keys included, for validation to report)
''
An Explode Array (PLAN ยง11.20): its column, its path of keys and its new column's name, always written, exactly as held (
''and empty keys included, for validation to report)