Reading in a loop

A query or Todo.get inside a for loop is a compile error, because it would read once per item. Read the whole set with one query using in instead:

// domains/planning/queries/todos_by_ids.jadpoquery todos_by_ids(todo_ids: List<Todo.id>) -> List<TodoView> {    from: Todo    where: Todo.id in todo_ids    order: [Todo.created_at asc]    limit: 100}

Writes inside a loop are allowed: the list is bounded, and every write joins the action's transaction.

An outside call inside a loop isn't allowed (Loops). A loop of calls is batches.each (How a run is kept). A batch that should keep its partial progress is a schedule or subscriber handling one item per action.