p28 - Defect in example code

[sebrose]

Steps to reproduce:

• Choose to "Hide complete items"
• Choose "Complete items"
• Hit return
• All previously completed items are now marked as incomplete

One possible solution:

function promptComplete() : void {

  ...

        collection.getTodoItems(true).forEach(item =>
            (!showCompleted && item.complete) ||
                collection.markComplete(item.id, completedTasks.find(id => id === item.id) != undefined))

  ...

}