add method
Add another string to be processed, returns the counts collection. filterNonChars removes non-chars from count.
Implementation
Map<String, int> add(String str, {bool filterNonChars = true}) {
allCharFrequency(str, filterNonChars: filterNonChars).forEach((key, val) {
_counts.update(key, (val1) => val1 + val, ifAbsent: () => val);
});
return _counts;
}