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select(+Map0, ++KeyList, -Map)
Creates a new map containing just those entries corresponding to a given list of keys.
- A map
- A list of keys to select
- The resulting map
The map Map contains the key/value pairs from the map Map0 where
the key appears in the list KeyList. Keys in KeyList which do not
appear in Map0 are ignored.
This predicate should only be called with maps created by other
predicates from the map module.