ConvertingComparator<S, T> constructor
ConvertingComparator<S, T> (
- Comparator<
T> _comparator, - Converter<
S, T> _converter
A comparator that compares source values of type S
by first converting them
to another type T
using a Converter, then applying a Comparator
on T
.
This is useful when you want to sort values based on a derived property or a type transformation.
🔧 Example: Compare strings by their lengths
final comparator = ConvertingComparator<String, int>(
Comparator.naturalOrder(),
Converter<String, int>((s) => s.length),
);
final list = ['pear', 'banana', 'kiwi'];
list.sort(comparator); // ['kiwi', 'pear', 'banana']
You can also use the factory constructors:
🔧 Using withConverter
and a ConversionService:
final service = DefaultConversionService();
final comparator = ConvertingComparator.withConverter<String, int>(
Comparator.naturalOrder(),
service,
Class<int>(),
);
Implementation
ConvertingComparator(this._comparator, this._converter);