subtractObject method
Subtracts duration specified by a map.
Implementation
Hora subtractObject(Map<String, dynamic> map) {
// Negate all values
final negated = <String, dynamic>{};
for (final entry in map.entries) {
final value = entry.value;
if (value is num) {
negated[entry.key] = -value;
}
}
return addObject(negated);
}