# changesSince method

1. @override

PropertyValues changesSince(

1. PropertyValues old

)
override

Computes the set of properties that differ compared to another `old` PropertyValues.

This method is useful for detecting changes between two property sets, such as during configuration updates or hot reload.

`old`: The previous property values to compare against Returns a new PropertyValues containing only the changed properties

Example:

    final old = MutablePropertyValues()
      ..addPropertyValueByName('host', '127.0.0.1');
    final current = MutablePropertyValues()
      ..addPropertyValueByName('host', 'localhost');

    final diff = current.changesSince(old);
    print(diff.getPropertyValue('host')?.value); // 'localhost'

## Implementation

    @override
    PropertyValues changesSince(PropertyValues old) {
      final changes = MutablePropertyValues();
      if (identical(this, old)) {
        return changes;
      }

      // Add new or changed properties
      for (final newPv in _values) {
        final oldPv = old.getPropertyValue(newPv.getName());
        if (oldPv == null || !oldPv.equals(newPv)) {
          changes.addPropertyValue(newPv);
        }
      }

      return changes;
    }