Append new tag to the end, skipping check if it already exists. O(1)
Remove all tags
Provides opportunity to iterate over tags.
Hash-like access to tags. Time complexity is O(number of tags).
If tag with such key is not found, returned value 'is nothing'.
If key length is different from 2, exception is thrown.
Special case when value represents nothing is used for removing tag
(assuming that no more than one with this key is presented in the record).
Number of tags. O(number of tags)
Returns the number of tags. Time complexity is O(number of tags)
Lazy tag storage.
Provides hash-like access and opportunity to iterate storage like an associative array.