public static ICollection <U> Transform <T, U>(ICollection <T> target, CollectionUtils.Functor
<T, U> functor)
{
ICollection <U> result = new AList <U>();
foreach (T element in target)
{
U mapped = functor.Invoke(element);
if (mapped != null)
{
result.AddItem(mapped);
}
}
return(result);
}
// Calls the block on every attachment dictionary. The block can return a different dictionary,
// which will be replaced in the rev's properties. If it returns nil, the operation aborts.
// Returns YES if any changes were made.
public virtual bool MutateAttachments(CollectionUtils.Functor <IDictionary <string,
object>, IDictionary <string, object> > functor)
{
{
IDictionary <string, object> properties = GetProperties();
IDictionary <string, object> editedProperties = null;
IDictionary <string, object> attachments = (IDictionary <string, object>)properties
.Get("_attachments");
IDictionary <string, object> editedAttachments = null;
foreach (string name in attachments.Keys)
{
IDictionary <string, object> attachment = (IDictionary <string, object>)attachments
.Get(name);
IDictionary <string, object> editedAttachment = functor.Invoke(attachment);
if (editedAttachment == null)
{
return(false);
}
// block canceled
if (editedAttachment != attachment)
{
if (editedProperties == null)
{
// Make the document properties and _attachments dictionary mutable:
editedProperties = new Dictionary <string, object>(properties);
editedAttachments = new Dictionary <string, object>(attachments);
editedProperties.Put("_attachments", editedAttachments);
}
editedAttachments.Put(name, editedAttachment);
}
}
if (editedProperties != null)
{
SetProperties(editedProperties);
return(true);
}
return(false);
}
}
