package dolmen

The type of immutable maps from tags to values.

A tag containing values of type 'a.

Are two tag keys equal ?

The empty map.

Create a new tag.

Get the list of values associated to a tag (can be the empty list).

Return the last value associated to a tag (i.e. the head of the list returned by get if it exists).

Add a value to a tag in a map. If some values were previously bound, this adds the new value to the head of the value list.

Replace the set of values associated to a tag in a map.