Function transformMap

transformMap<K, V, R>(
source: ReadonlyMap<K, V>,
transformer: (value: V, key: K) => R,
): Map<K, R>
Like Array.map, but for a Map. Transforms from Map<K,V> to Map<K,R>, returning as a new Map.
Type Parameters
- K
  Type of keys (generally a string)
- V
  Type of input map values
- R
  Type of output map values
Parameters
- source: ReadonlyMap<K, V>
- transformer: (value: V, key: K) => R
Returns Map<K, R>
Example
```
const mapOfStrings = new Map();
mapOfStrings.set(`a`, `10`);
mapOfStrings.get(`a`); // Yields `10` (a string)

// Convert a map of string->string to string->number
const mapOfInts = transformMap(mapOfStrings, (value, key) => parseInt(value));

mapOfInts.get(`a`); // Yields 10 (a proper number)
```
If you want to combine values into a single object, consider instead mapToObjectTransform.