Mapping

We may want to change all the values of a given map by applying to them a function. This is called a map operation, not to be confused with the map data structure. The predefined functional iterator implementing the mapped operation over maps is called Map.map. It takes a binding, that is, a key and its associated value in the map, and computes a new value for that key.

In the following example, from a map from integers to integers is made a map whose values are the sum of the keys and values of each binding.

const my_map: map<int,int> = Map.literal(list([[0,0], [1,1], [2,2]]));

// plus_one == Map.literal(list([[0,0],[1,2],[2,4]]))

const plus_one = Map.map(([k,v]) => k + v, my_map);

Note: See the predefined namespace Map