getAsNullableDuration method
Converts map element into a Duration or returns null if conversion is not possible.
key
a key of element to get. Returns Duration value of the element or null if conversion is not supported.
See DurationConverter.toNullableDuration
Implementation
Duration? getAsNullableDuration(String key) {
var value = get(key);
return DurationConverter.toNullableDuration(value);
}