toArticles.kt

fun Iterable<ResultRow>.toArticles(): List<Article> {
   return fold(mutableMapOf<ArticleId, Article>()) { map, resultRow ->
       val article = resultRow.toArticle()
       val tagId = resultRow.tryGet(ArticleTagTable.tagId)
       val tag = tagId?.let { resultRow.toTag() }
       val current = map.getOrDefault(article.id, article)
       map[article.id] = current.copy(tags = current.tags + listOfNotNull(tag))
       map
   }.values.toList()
}