MutableMap::map
Returns a MutableMap after an operation has been applied to each value
in the current MutableMap
public function map<Tu>(
(function(Tv): Tu) $fn,
): MutableMap<Tk, Tu>;
Every value in the current Map is affected by a call to map(), unlike
filter() where only values that meet a certain criteria are affected.
The keys will remain unchanged from the current MutableMap to the
returned MutableMap.
Guide
Parameters
(function(Tv): Tu) $fn- The callback containing the operation to apply to the currentMutableMapvalues.
Returns
MutableMap<Tk,Tu>- aMutableMapcontaining key/value pairs after a user-specified operation is applied.