It seems as if Arrow expects for some vectors to be empty rather than null. (Examples: Footer.dictionaries, Field.children)
Anyone using --gen-object-api with flatc will get code that writes null when (e.g.) _o->children.size() is zero in CreateField(). I may be missing something but I don't see a way to change this behavior in flatc. I understand that the object API is not as performant, but wanted to toss out the question: Do we want to tolerate null vectors as well as empty vectors so that other writer implementations have this option? E.g. if they choose to use --gen-object-api ? -John
