-table(table table-bordered table-condensed).
-|_. collection state|_. is_trashed|_. trash_at|_. delete_at|_. get|_. index|_. index?include_trash=true|_. can be modified|
-|persisted collection|false |null |null |yes |yes |yes |yes |
-|expiring collection|false |future |future |yes |yes |yes |yes |
-|trashed collection|true |past |future |no |no |yes |only is_trashed, trash_at and delete_at attribtues|
-|deleted collection|true|past |past |no |no |no |no |