🤰🏻 😈 ↖️ Dart: Fast Immutable Collections 🙎🏼 🎂 ⛹️

Hey! I present to your attention a translation of an article about the capabilities of the FIC package (Fast Immutable Collections). FIC is a competitor for packages like built_collection and kt_dart, but it is much faster and easier to use.

Original

, , , , Dart (List), - , ..

var list = [1, 2];
list.add(3); // list: [1, 2, 3].

List.unmodifiable

, , , add

, , :

var list = List.unmodifiable([1, 2]);
list.add(3); //     .

var list = List.unmodifiable([1, 2]); //    .
var newList = list.toList()..add(3);

print(newList); // [1, 2, 3].

, List

, , . , : IList

List. IList

- , API .

IList

extension- lock

List

:

IList<int> iList = [1, 2].lock;

IList

. add

IList

:

var myList = [1, 2].lock; //    .
var newList = myList.add(3));
print(myList); // [1, 2].
print(newList); // [1, 2, 3].

FIC

FIC (Fast Immutable Collections, ) . FIC - built_collection kt_dart, .

. FIC , Dart:

Time required to add 1,000 items to a list of 10,000 items. Less is better — , 1 000 10 000 . ,

IList

, ISet

IMap

. , "" :

IList<int> iList = [1, 2].lock;
ISet<int> iSet = {1, 2}.lock;
IMap<String, int> iMap = {"a": 1, "b": 2}.lock;

Iterable

(List) (Set) toIList()

toISet()

, :

IList<int> iList = myIterable.toIList();
ISet<int> iSet = myIterable.toISet();
//   :
IList<int> iList = IList(myIterable);
ISet<int> iSet = ISet(myIterable);

"" :

List<int> list = iList.unlock;
Set<int> set = iSet.unlock;
Map<String, int> map = iMap.unlock;
//   :
List<int> list = iList.toList();
Set<int> set = iSet.toSet();
//   :
List<int> list = List.of(iList);
Set<int> set = Set.of(iSet);

, , . :

var iList1 = [1, 2].lock;          
var iList2 = iList1.add(3); // [1, 2, 3].
var iList3 = iList2.remove(2); // [1, 3].         
print(iList1); //   [1, 2].

var iList = [1, 2, 3].lock.add(4).remove(2); // [1, 3, 4].

, FIC , :

var iList1 = [1, 2].lock;
var iList2 = [1, 2].lock;
print(identical(iList1, iList2)); // false.
print(iList1 == iList2); // true.

(List), :

var list1 = [1, 2];
var list2 = [1, 2];
var list3 = list1;
//  (List)   :
print(identical(list1, list2)); // false.
print(identical(list1, list3)); // true.
print(list1 == list2); // false.
//     ILists   :
print(list1.lock == list2.lock); // true.

, IList

. IList

, :

//  ILists   :
var iList1 = [1, 2].lock;
var iList2 = [1, 2].lock;
print(iList1 == iList2); // true.
//    ILists   :
var iList3 = [1, 2].lock.withIdentityEquals;
var iList4 = [1, 2].lock.withIdentityEquals;
print(iList3 == iList4); // false.

ISet

IMap

, , :

var iSet = {2, 4, 1, 9, 3}.lock;  
print(iSet.join(", ")); // [2, 4, 1, 9, 3].
var iSet = {2, 4, 1, 9, 3}.lock.withConfig(ConfigSet(sort: true));
print(iSet.join(", ")); // [1, 2, 3, 4, 9].

IMapOfSets

Map<K, V>

, IMap<K, V>

.

Map<K, Set<V>>

IMapOfSets<K, V>

:

// Map  IMap.
IMap<K, V> map = {'a': 1, 'b': 2}.lock;
// Map  IMapOfSets.
IMapOfSets<K, V> map = {'a': {1, 2}, 'b': {3, 4}}.lock;

"Map of sets" - (multimap). IMapOfSets

, (sets), .

IMapOfSets<K, V> map = {'a': {1, 2}, 'b': {3, 4}}.lock;
print(map.add('a', 3)); // {'a': {1, 2, 3}, 'b': {3, 4}}.

, StudentsPerCourse

, . . (map), , - .

ListSet

, FIC . , ListSet

:

, (Set) .
(List) , :

ListSet<int> listSet = ListSet.of([1, 2, 3]);
expect(listSet[2], 3);
expect(listSet.contains(2), isTrue);
List<int> list = listSet;
Set<int> set = listSet;
expect(list[2], 3);
expect(set.contains(2), isTrue);

ListSet

Set

LinkedHashSet

, ListSet

. ListSet

, List

. , .

, , , ListSet

, LinkedHashSet

- . ListSet

List

, Set

. , , sort , LinkedHashSet

List

, , Set

.

,

FIC :

Iterable :

combineIterables

- , Iterable

.
Iterable.isNullOrEmpty

, Iterable.isNotNullOrEmpty

Iterable.isEmptyButNotNull

.
Iterable.deepEquals

==

.
Iterable.deepEqualsByIdentity

identical

.
Iterable.findDuplicates

Set

.
Iterable.removeNulls

, null

, Iterable

.
Iterable.removeDuplicates

. , by . removeNulls

true

, null-.
Iterable.sortedLike

, Iterable

. , Iterable

, .

List

:

List.sortOrdered

sort

, (merge sort). sort

, orderedSort

, , , , .
List.sortLike

ordering Iterable

. , ordering, .
List.moveToTheFront

.
List.moveToTheEnd

.
List.whereMoveToTheFront

, , .
List.whereMoveToTheEnd

, , .
List.toggle

, true

. , false

.
List.compareAsSets

true ( ). .
List.mapIndexed

. .
List.splitList

, .
List.divideList

, .
List.addBetween

, .
List.concat

5 .
List.splitByLength

length

.
List.update

, .
List.distinct

, .
List.reversedView

.