From 4d3102ffd8befe14ccc13b902f8f6d35598a1c6c Mon Sep 17 00:00:00 2001
From: Simon Leier <simonleier@gmail.com>
Date: Mon, 29 Nov 2021 23:46:58 +0100
Subject: [PATCH 1/6] Bump to 1.0

---
 CHANGELOG.md            |  4 ++++
 README.md               | 22 ----------------------
 lib/src/function.dart   |  6 ------
 lib/src/string.dart     | 12 ------------
 pubspec.yaml            |  2 +-
 test/function_test.dart |  9 ---------
 test/string_test.dart   |  9 ---------
 7 files changed, 5 insertions(+), 59 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index dd113c6..f4227ee 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 1.0.0
+- Promote to stable version
+- Remove deprecated extensions
+
 ## 0.8.0
 
 - [PR-136](https://github.com/leisim/dartx/pull/136) New: Multiple extensions for `Map`. `all()`, `any()`, `count()`, `filter()`, `filterKeys()`, `filterNot`, `filterValues`, `getOrElse()`, `mapEntries()`, `mapKeys()`, `mapValues()`, `maxBy()`, `maxWith()`, `minBy()`, `minWith`, `none()`, `toList()`, `toMap()`, `orEmpty()`
diff --git a/README.md b/README.md
index 85b5251..1722ed9 100644
--- a/README.md
+++ b/README.md
@@ -104,16 +104,6 @@ final word = 'abcd'.capitalize(); // Abcd
 final anotherWord = 'Abcd'.capitalize(); // Abcd
 ```
 
-### .chars - DEPRECATED
-
-Use `.characters` from the official characters package.
-
-Get a list of single character strings from a string. Supports emojis.
-
-```dart
-final chars = 'family👨‍👨‍👧‍👦'.chars; // ['f', 'a', 'm', 'i', 'l', 'y', '👨‍👨‍👧‍👦']
-```
-
 ### .decapitalize
 
 Returns a copy of the string having its first letter lowercased, or the original string, if it's empty or already starts with a lower case letter.
@@ -366,18 +356,6 @@ for (final i in 10.rangeTo(2).step(2)) {
 
 ## Function
 
-### .invoke() - DEPRECATED
-
-Use `call()` instead. This is very useful for `null` checks.
-
-```dart
-final func = (String value) {
-  print(value);
-}
-
-func?.call('hello world');
-```
-
 ### .partial(), .partial2() ...
 
 Applies some of the required arguments to a function and returns a function which takes the remaining arguments.
diff --git a/lib/src/function.dart b/lib/src/function.dart
index c0bd209..9b00da3 100644
--- a/lib/src/function.dart
+++ b/lib/src/function.dart
@@ -6,12 +6,6 @@ typedef Function2<A, B, R> = R Function(A a, B b);
 typedef Function3<A, B, C, R> = R Function(A a, B b, C c);
 typedef Function4<A, B, C, D, R> = R Function(A a, B b, C c, D d);
 
-extension Function0InvokeExtension<R> on Function0<R> {
-  /// Invokes this function and returns it's return value.
-  @Deprecated('Use `call()`')
-  R invoke() => this();
-}
-
 extension Function1InvokeExtensions<A, R> on Function1<A, R> {
   /// Invokes this function and returns it's return value.
   R invoke(A first) => this(first);
diff --git a/lib/src/string.dart b/lib/src/string.dart
index 9ab6525..47fa254 100644
--- a/lib/src/string.dart
+++ b/lib/src/string.dart
@@ -3,18 +3,6 @@ part of dartx;
 const _ascii = 0x007f;
 const _latin1 = 0x00ff;
 
-extension StringCharsExtension on String {
-  /// The characters of a string.
-  ///
-  /// A character is a Unicode Grapheme cluster represented by a substring of
-  /// the original string.
-  ///
-  /// Please use [StringCharacters].characters
-  /// https://github.com/dart-lang/characters/blob/10527437926f1b454edf9912fe700aa2506b1c3d/lib/src/extensions.dart#L9
-  @Deprecated('Use .characters from the official characters package')
-  Iterable<String> get chars => characters.Characters(this);
-}
-
 extension StringCapitalizeExtension on String {
   /// Returns a copy of this string having its first letter uppercased, or the
   /// original string, if it's empty or already starts with an upper case
diff --git a/pubspec.yaml b/pubspec.yaml
index 7f7f9f0..6da749b 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: dartx
 description: Superpowers for Dart. Collection of useful static extension methods.
-version: 0.8.0
+version: 1.0.0
 homepage: https://github.com/leisim/dartx
 
 environment:
diff --git a/test/function_test.dart b/test/function_test.dart
index 3c9b5ab..649cc01 100644
--- a/test/function_test.dart
+++ b/test/function_test.dart
@@ -4,15 +4,6 @@ import 'package:test/test.dart';
 
 void main() {
   group('Function', () {
-    group('Function0X', () {
-      final func = () => 5;
-
-      test('.invoke', () {
-        // ignore: deprecated_member_use_from_same_package
-        expect(func.invoke(), 5);
-      });
-    });
-
     group('Function1X', () {
       final func = (String s) => s;
 
diff --git a/test/string_test.dart b/test/string_test.dart
index 26d8147..6a5aed5 100644
--- a/test/string_test.dart
+++ b/test/string_test.dart
@@ -5,15 +5,6 @@ import 'package:test/test.dart';
 
 void main() {
   group('StringX', () {
-    test('.chars', () {
-      // ignore: deprecated_member_use_from_same_package
-      expect('test12'.chars, ['t', 'e', 's', 't', '1', '2']);
-      expect('test12'.characters, ['t', 'e', 's', 't', '1', '2']);
-      // ignore: deprecated_member_use_from_same_package
-      expect('ഐ⌛酪Б👨‍👨‍👧‍👦'.chars, ['ഐ', '⌛', '酪', 'Б', '👨‍👨‍👧‍👦']);
-      expect('ഐ⌛酪Б👨‍👨‍👧‍👦'.characters, ['ഐ', '⌛', '酪', 'Б', '👨‍👨‍👧‍👦']);
-    });
-
     test('.capitalize()', () {
       expect(''.capitalize(), '');
       expect('123'.capitalize(), '123');

From ab7b5ad35e8e3d7302e41d83df08683a04f59e53 Mon Sep 17 00:00:00 2001
From: David LJ <david.lozanojarque@koahealth.com>
Date: Fri, 17 Dec 2021 11:25:48 +0100
Subject: [PATCH 2/6] refactor: iterable extension Forth -> Fourth

---
 lib/src/iterable.dart | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/src/iterable.dart b/lib/src/iterable.dart
index 1b17168..e9b1704 100644
--- a/lib/src/iterable.dart
+++ b/lib/src/iterable.dart
@@ -18,7 +18,7 @@ extension IterableThirdItem<E> on Iterable<E> {
   E get third => elementAt(2);
 }
 
-extension IterableForthItem<E> on Iterable<E> {
+extension IterableFourthItem<E> on Iterable<E> {
   /// Fourth element.
   ///
   /// ```dart

From 430cb04d27bd857a2cd7d3a3191ffa5d33200dd9 Mon Sep 17 00:00:00 2001
From: Konstantin Pelz <Konstantin.pelz@posteo.de>
Date: Tue, 21 Dec 2021 11:47:51 +0100
Subject: [PATCH 3/6] #150 add String.isNullOrBlank and String.isNotNullOrBlank

---
 README.md             | 24 ++++++++++++++++++++++++
 lib/src/string.dart   | 10 ++++++++++
 test/string_test.dart | 16 ++++++++++++++++
 3 files changed, 50 insertions(+)

diff --git a/README.md b/README.md
index 1722ed9..8148a50 100644
--- a/README.md
+++ b/README.md
@@ -207,6 +207,30 @@ final isBlank = ' '.isNullOrEmpty; // false
 final isLineBreak = '\n'.isNullOrEmpty; // false
 ```
 
+### .isNullOrBlank
+
+Returns `true` if the String is either `null` or blank.
+
+```dart
+final isNull = null.isNullOrBlank; // true
+final isEmpty = ''.isNullOrBlank; // true
+final isBlank = ' '.isNullOrBlank; // true
+final isLineBreak = '\n'.isNullOrBlank; // true
+final isFoo = ' foo '.isNullOrBlank; // false
+```
+
+### .isNotNullOrBlank
+
+Returns `true` if the String is neither `null` nor blank.
+
+```dart
+final isNull = null.isNullOrBlank; // true
+final isEmpty = ''.isNullOrBlank; // true
+final isBlank = ' '.isNullOrBlank; // true
+final isLineBreak = '\n'.isNullOrBlank; // true
+final isFoo = ' foo '.isNullOrBlank; // true
+```
+
 ### .isUpperCase
 
 Returns `true` if the entire string is upper case.
diff --git a/lib/src/string.dart b/lib/src/string.dart
index 47fa254..1f2d561 100644
--- a/lib/src/string.dart
+++ b/lib/src/string.dart
@@ -254,3 +254,13 @@ extension NullableStringIsNotNullOrEmptyExtension on String? {
   /// Returns `true` if the string is neither null nor empty.
   bool get isNotNullOrEmpty => !isNullOrEmpty;
 }
+
+extension NullableStringIsNullOrBlankExtension on String? {
+  /// Returns `true` if the string is either `null` or blank.
+  bool get isNullOrBlank => this?.isBlank ?? true;
+}
+
+extension NullableStringIsNotNullOrBlankExtension on String? {
+  /// Returns `true` if the string is neither null nor blank.
+  bool get isNotNullOrBlank => !isNullOrBlank;
+}
diff --git a/test/string_test.dart b/test/string_test.dart
index 6a5aed5..a2d0e49 100644
--- a/test/string_test.dart
+++ b/test/string_test.dart
@@ -161,6 +161,22 @@ void main() {
       expect('\n'.isNotNullOrEmpty, true);
     });
 
+    test('.isNullOrBlank', () {
+      expect(null.isNullOrBlank, true);
+      expect(''.isNullOrBlank, true);
+      expect(' '.isNullOrBlank, true);
+      expect('\n'.isNullOrBlank, true);
+      expect(' foo '.isNullOrBlank, false);
+    });
+
+    test('.isNotNullOrBlank', () {
+      expect(null.isNotNullOrBlank, false);
+      expect(''.isNotNullOrBlank, false);
+      expect(' '.isNotNullOrBlank, false);
+      expect('\n'.isNotNullOrBlank, false);
+      expect(' foo '.isNotNullOrBlank, true);
+    });
+
     test('.toUtf8()', () {
       expect(''.toUtf8(), []);
       expect('hello'.toUtf8(), [104, 101, 108, 108, 111]);

From c26758d04fdeeaafdaa6db20412fe9a09b1577fe Mon Sep 17 00:00:00 2001
From: Biplab Dutta <biplabdutta860@gmail.com>
Date: Sat, 5 Mar 2022 00:31:52 +0545
Subject: [PATCH 4/6] feat: obtain an ordinal number of type String for any
 integer (#153)

---
 README.md          | 11 +++++++++++
 lib/dartx.dart     |  1 +
 lib/src/int.dart   | 29 +++++++++++++++++++++++++++++
 test/int_test.dart | 27 +++++++++++++++++++++++++++
 4 files changed, 68 insertions(+)
 create mode 100644 lib/src/int.dart
 create mode 100644 test/int_test.dart

diff --git a/README.md b/README.md
index 1722ed9..4b973d0 100644
--- a/README.md
+++ b/README.md
@@ -93,6 +93,17 @@ final increasingSubSequences = list.chunkWhile((a, b) => a + 1 == b);
 `splitWhen` is the opposite of `chunkWhile` that starts a new chunk every time
 the predicate _didn't_ match.
 
+## int
+
+### .ordinal
+
+Returns an ordinal number of `String` type for any integer
+
+```dart
+final a = 1.ordinal();  // 1st
+final b = 108.ordinal();  // 108th
+```
+
 ## String
 
 ### .capitalize
diff --git a/lib/dartx.dart b/lib/dartx.dart
index 4966351..4b59fe3 100644
--- a/lib/dartx.dart
+++ b/lib/dartx.dart
@@ -17,6 +17,7 @@ part 'src/arithmetic.dart';
 part 'src/comparable.dart';
 part 'src/comparator.dart';
 part 'src/function.dart';
+part 'src/int.dart';
 part 'src/iterable.dart';
 part 'src/iterable_num.dart';
 part 'src/list.dart';
diff --git a/lib/src/int.dart b/lib/src/int.dart
new file mode 100644
index 0000000..2fdb3bb
--- /dev/null
+++ b/lib/src/int.dart
@@ -0,0 +1,29 @@
+part of dartx;
+
+extension Ordinals<T extends int> on T {
+  /// Returns an ordinal number of `String` type for any integer
+  ///
+  /// ```dart
+  /// 101.ordinal(); // 101st
+  ///
+  /// 999218.ordinal(); // 999218th
+  /// ```
+  String ordinal() {
+    final onesPlace = this % 10;
+    final tensPlace = ((this / 10).floor()) % 10;
+    if (tensPlace == 1) {
+      return '${this}th';
+    } else {
+      switch (onesPlace) {
+        case 1:
+          return '${this}st';
+        case 2:
+          return '${this}nd';
+        case 3:
+          return '${this}rd';
+        default:
+          return '${this}th';
+      }
+    }
+  }
+}
diff --git a/test/int_test.dart b/test/int_test.dart
new file mode 100644
index 0000000..9fac7bd
--- /dev/null
+++ b/test/int_test.dart
@@ -0,0 +1,27 @@
+import 'package:dartx/dartx.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group(
+    'intX',
+    () {
+      test(
+        '.ordinal()',
+        () {
+          expect(0.ordinal(), '0th');
+          expect(1.ordinal(), '1st');
+          expect(2.ordinal(), '2nd');
+          expect(3.ordinal(), '3rd');
+          expect(4.ordinal(), '4th');
+          expect(10.ordinal(), '10th');
+          expect(101.ordinal(), '101st');
+          expect(102.ordinal(), '102nd');
+          expect(103.ordinal(), '103rd');
+          expect(111.ordinal(), '111th');
+          expect(112.ordinal(), '112th');
+          expect(113.ordinal(), '113th');
+        },
+      );
+    },
+  );
+}

From 7acc45f6965d4c2486338448057617896d291737 Mon Sep 17 00:00:00 2001
From: Pascal Welsch <pascal@welsch.dev>
Date: Fri, 4 Mar 2022 20:08:59 +0100
Subject: [PATCH 5/6] Make SortedList a public API

It is exposed so it should be public. (Constructor is private anyways)
---
 lib/src/iterable.dart    | 12 ++++++------
 lib/src/sorted_list.dart | 18 +++++++++---------
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/lib/src/iterable.dart b/lib/src/iterable.dart
index 1b17168..efac6a6 100644
--- a/lib/src/iterable.dart
+++ b/lib/src/iterable.dart
@@ -277,8 +277,8 @@ extension IterableSortedBy<E> on Iterable<E> {
   ///
   /// **Note:** The actual sorting is performed when an element is accessed for
   /// the first time.
-  _SortedList<E> sortedBy(Comparable Function(E element) selector) {
-    return _SortedList<E>._withSelector(this, selector, 1, null);
+  SortedList<E> sortedBy(Comparable Function(E element) selector) {
+    return SortedList<E>._withSelector(this, selector, 1, null);
   }
 }
 
@@ -292,8 +292,8 @@ extension IterableSortedByDescending<E> on Iterable<E> {
   ///
   /// **Note:** The actual sorting is performed when an element is accessed for
   /// the first time.
-  _SortedList<E> sortedByDescending(Comparable Function(E element) selector) {
-    return _SortedList<E>._withSelector(this, selector, -1, null);
+  SortedList<E> sortedByDescending(Comparable Function(E element) selector) {
+    return SortedList<E>._withSelector(this, selector, -1, null);
   }
 }
 
@@ -306,8 +306,8 @@ extension IterableSortedWith<E> on Iterable<E> {
   ///
   /// **Note:** The actual sorting is performed when an element is accessed for
   /// the first time.
-  _SortedList<E> sortedWith(Comparator<E> comparator) {
-    return _SortedList<E>._(this, comparator);
+  SortedList<E> sortedWith(Comparator<E> comparator) {
+    return SortedList<E>._(this, comparator);
   }
 }
 
diff --git a/lib/src/sorted_list.dart b/lib/src/sorted_list.dart
index 2a705ed..2e24765 100644
--- a/lib/src/sorted_list.dart
+++ b/lib/src/sorted_list.dart
@@ -12,17 +12,17 @@ Comparator<E> _getComparator<E>(
   return parent?.compose(newComparator) ?? newComparator;
 }
 
-class _SortedList<E> extends _DelegatingList<E> {
+class SortedList<E> extends _DelegatingList<E> {
   final Iterable<E> _source;
   final Comparator<E> _comparator;
   List<E>? _sortedResults;
 
-  _SortedList._(
+  SortedList._(
     this._source,
     this._comparator,
   );
 
-  _SortedList._withSelector(
+  SortedList._withSelector(
     this._source,
     Comparable Function(E element) selector,
     int order,
@@ -44,8 +44,8 @@ class _SortedList<E> extends _DelegatingList<E> {
   ///
   /// **Note:** The actual sorting is performed when an element is accessed for
   /// the first time.
-  _SortedList<E> thenBy(Comparable Function(E element) selector) {
-    return _SortedList<E>._withSelector(this, selector, 1, _comparator);
+  SortedList<E> thenBy(Comparable Function(E element) selector) {
+    return SortedList<E>._withSelector(this, selector, 1, _comparator);
   }
 
   /// Returns a new list with all elements sorted according to previously
@@ -54,8 +54,8 @@ class _SortedList<E> extends _DelegatingList<E> {
   ///
   /// **Note:** The actual sorting is performed when an element is accessed for
   /// the first time.
-  _SortedList<E> thenByDescending(Comparable Function(E element) selector) {
-    return _SortedList<E>._withSelector(this, selector, -1, _comparator);
+  SortedList<E> thenByDescending(Comparable Function(E element) selector) {
+    return SortedList<E>._withSelector(this, selector, -1, _comparator);
   }
 
   /// Returns a new list with all elements sorted according to previously
@@ -63,8 +63,8 @@ class _SortedList<E> extends _DelegatingList<E> {
   ///
   /// **Note:** The actual sorting is performed when an element is accessed for
   /// the first time.
-  _SortedList<E> thenWith(Comparator<E> comparator) {
-    return _SortedList<E>._(this, _comparator.compose(comparator));
+  SortedList<E> thenWith(Comparator<E> comparator) {
+    return SortedList<E>._(this, _comparator.compose(comparator));
   }
 
   @override

From c4314bc0897818e3902368494f92cbd35dfbaf79 Mon Sep 17 00:00:00 2001
From: Pascal Welsch <pascal@welsch.dev>
Date: Fri, 4 Mar 2022 20:09:10 +0100
Subject: [PATCH 6/6] Use isEven/isOdd

---
 test/iterable_test.dart    | 40 +++++++++++++++++++-------------------
 test/map_test.dart         |  2 +-
 test/range_test.dart       |  4 ++--
 test/sorted_list_test.dart |  8 ++++----
 4 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/test/iterable_test.dart b/test/iterable_test.dart
index 1017278..f43cc6c 100644
--- a/test/iterable_test.dart
+++ b/test/iterable_test.dart
@@ -178,7 +178,8 @@ void main() {
 
       expect(list1.contentEquals(list2.toList()), false);
       expect(list1.contentEquals(list2), false);
-      bool compareCodeUnits(e1, e2) => e1.codeUnitAt(0) == e2.codeUnitAt(0);
+      bool compareCodeUnits(String e1, String e2) =>
+          e1.codeUnitAt(0) == e2.codeUnitAt(0);
       expect(list1.contentEquals(list2, compareCodeUnits), true);
       expect(list3.contentEquals(list4), false);
       expect(list4.contentEquals(list3), false);
@@ -370,7 +371,7 @@ void main() {
     });
 
     test('.filterIndexed()', () {
-      final result = [6, 5, 4, 3, 2, 1, 0].filter((it) => it % 2 == 0);
+      final result = [6, 5, 4, 3, 2, 1, 0].filter((it) => it.isEven);
       expect(result, [6, 4, 2, 0]);
     });
 
@@ -387,7 +388,7 @@ void main() {
 
     test('.filterTo()', () {
       final list = <int>[];
-      [1, 2, 3, 4, 3, 2, 1].filterTo(list, (e) => e % 2 == 0);
+      [1, 2, 3, 4, 3, 2, 1].filterTo(list, (e) => e.isEven);
       expect(list, [2, 4, 2]);
     });
 
@@ -396,13 +397,13 @@ void main() {
       final list = <int>[];
       [1, 2, 3, 4, 3, 2, 1].filterIndexedTo(list, (e, i) {
         expect(index++, i);
-        return e % 2 == 0;
+        return e.isEven;
       });
       expect(list, [2, 4, 2]);
     });
 
     test('.filterNot()', () {
-      expect([1, 2, 3, 4, 3, 2, 1].filterNot((e) => e % 2 == 0), [1, 3, 3, 1]);
+      expect([1, 2, 3, 4, 3, 2, 1].filterNot((e) => e.isEven), [1, 3, 3, 1]);
     });
 
     test('.filterNotIndexed()', () {
@@ -410,7 +411,7 @@ void main() {
       expect(
         [1, 2, 3, 4, 3, 2, 1].filterNotIndexed((e, i) {
           expect(index++, i);
-          return e % 2 == 0;
+          return e.isEven;
         }),
         [1, 3, 3, 1],
       );
@@ -418,7 +419,7 @@ void main() {
 
     test('.filterNotTo()', () {
       final list = <int>[];
-      [1, 2, 3, 4, 3, 2, 1].filterNotTo(list, (e) => e % 2 == 0);
+      [1, 2, 3, 4, 3, 2, 1].filterNotTo(list, (e) => e.isEven);
       expect(list, [1, 3, 3, 1]);
     });
 
@@ -427,7 +428,7 @@ void main() {
       final list = <int>[];
       [1, 2, 3, 4, 3, 2, 1].filterNotToIndexed(list, (e, i) {
         expect(index++, i);
-        return e % 2 == 0;
+        return e.isEven;
       });
       expect(list, [1, 3, 3, 1]);
     });
@@ -449,7 +450,7 @@ void main() {
 
     test('.whereTo()', () {
       final list = <int>[];
-      [1, 2, 3, 4, 3, 2, 1].whereTo(list, (e) => e % 2 == 0);
+      [1, 2, 3, 4, 3, 2, 1].whereTo(list, (e) => e.isEven);
       expect(list, [2, 4, 2]);
     });
 
@@ -458,13 +459,13 @@ void main() {
       final list = <int>[];
       [1, 2, 3, 4, 3, 2, 1].whereIndexedTo(list, (e, i) {
         expect(index++, i);
-        return e % 2 == 0;
+        return e.isEven;
       });
       expect(list, [2, 4, 2]);
     });
 
     test('.whereNot()', () {
-      expect([1, 2, 3, 4, 3, 2, 1].whereNot((e) => e % 2 == 0), [1, 3, 3, 1]);
+      expect([1, 2, 3, 4, 3, 2, 1].whereNot((e) => e.isEven), [1, 3, 3, 1]);
     });
 
     test('.whereNotIndexed()', () {
@@ -472,7 +473,7 @@ void main() {
       expect(
         [1, 2, 3, 4, 3, 2, 1].whereNotIndexed((e, i) {
           expect(index++, i);
-          return e % 2 == 0;
+          return e.isEven;
         }),
         [1, 3, 3, 1],
       );
@@ -480,7 +481,7 @@ void main() {
 
     test('.whereNotTo()', () {
       final list = <int>[];
-      [1, 2, 3, 4, 3, 2, 1].whereNotTo(list, (e) => e % 2 == 0);
+      [1, 2, 3, 4, 3, 2, 1].whereNotTo(list, (e) => e.isEven);
       expect(list, [1, 3, 3, 1]);
     });
 
@@ -489,7 +490,7 @@ void main() {
       final list = <int>[];
       [1, 2, 3, 4, 3, 2, 1].whereNotToIndexed(list, (e, i) {
         expect(index++, i);
-        return e % 2 == 0;
+        return e.isEven;
       });
       expect(list, [1, 3, 3, 1]);
     });
@@ -506,7 +507,7 @@ void main() {
       expect([].mapNotNull((it) => 1), []);
       expect([1, 2, 3, 4].mapNotNull((it) => null), []);
       expect(
-        [1, 2, 3, 4].mapNotNull((it) => it % 2 == 0 ? it * 2 : null),
+        [1, 2, 3, 4].mapNotNull((it) => it.isEven ? it * 2 : null),
         [4, 8],
       );
     });
@@ -519,7 +520,7 @@ void main() {
       );
       expect([5, 4, null, 2].mapIndexed((index, it) => index), [0, 1, 2, 3]);
       expect(
-        [1, 2, 3, 4].mapIndexed((index, it) => it % 2 == 0 ? it * 2 : null),
+        [1, 2, 3, 4].mapIndexed((index, it) => it.isEven ? it * 2 : null),
         [null, 4, null, 8],
       );
     });
@@ -533,7 +534,7 @@ void main() {
       );
       expect(
         [1, 2, 3, 4]
-            .mapIndexedNotNull((index, it) => it % 2 == 0 ? it * 2 : null),
+            .mapIndexedNotNull((index, it) => it.isEven ? it * 2 : null),
         [4, 8],
       );
     });
@@ -925,8 +926,7 @@ void main() {
 
     test('groupBy', () {
       expect(
-        ['foo', 'bar', 'baz', 'bop', 'qux']
-            .groupBy((dynamic string) => string[1]),
+        ['foo', 'bar', 'baz', 'bop', 'qux'].groupBy((it) => it[1]),
         equals({
           'o': ['foo', 'bop'],
           'a': ['bar', 'baz'],
@@ -937,7 +937,7 @@ void main() {
 
     test('.partition()', () {
       expect([].partition((it) => false), <List<int>>[[], []]);
-      expect([1, 2, 3, 4, 5, 6].partition((it) => it % 2 == 1), [
+      expect([1, 2, 3, 4, 5, 6].partition((it) => it.isOdd), [
         [1, 3, 5],
         [2, 4, 6]
       ]);
diff --git a/test/map_test.dart b/test/map_test.dart
index 6777876..f8f9810 100644
--- a/test/map_test.dart
+++ b/test/map_test.dart
@@ -60,7 +60,7 @@ void main() {
 
       test('count even', () {
         final map = {1: 'a', 2: 'b', 3: 'c'};
-        expect(map.count((it) => it.key % 2 == 0), 1);
+        expect(map.count((it) => it.key.isEven), 1);
       });
     });
 
diff --git a/test/range_test.dart b/test/range_test.dart
index 3d0bc73..9ce6064 100644
--- a/test/range_test.dart
+++ b/test/range_test.dart
@@ -316,7 +316,7 @@ void main() {
       });
       test('lastWhere', () {
         final range = IntProgression(0, 9, step: 3);
-        bool isEven(it) => it % 2 == 0;
+        bool isEven(int it) => it.isEven;
         expect(range.last, 9);
         expect(range.lastWhere(isEven), 6);
       });
@@ -347,7 +347,7 @@ void main() {
       });
       test('firstWhere minds the predicate', () {
         final range = IntProgression(1, 10, step: 3);
-        bool isEven(it) => it % 2 == 0;
+        bool isEven(int it) => it.isEven;
         expect(range.first, 1);
         expect(range.firstWhere(isEven), 4);
       });
diff --git a/test/sorted_list_test.dart b/test/sorted_list_test.dart
index 4643012..5242949 100644
--- a/test/sorted_list_test.dart
+++ b/test/sorted_list_test.dart
@@ -43,7 +43,7 @@ void main() {
       expect(_sortedList.firstWhere((it) => it.isEven), 2);
     });
     test('fold', () {
-      expect(_sortedList.fold(0, (dynamic a, b) => a + b), 10);
+      expect(_sortedList.fold(0, (int a, b) => a + b), 10);
     });
     test('followedBy', () {
       expect(_sortedList.followedBy([2]), [1, 2, 3, 4, 2]);
@@ -108,7 +108,7 @@ void main() {
       expect(_sortedList.toSet(), {1, 2, 3, 4});
     });
     test('where', () {
-      expect(_sortedList.where((it) => it % 2 == 0), [2, 4]);
+      expect(_sortedList.where((it) => it.isEven), [2, 4]);
     });
     test('whereType', () {
       expect(_sortedList.whereType<int>(), [1, 2, 3, 4]);
@@ -211,7 +211,7 @@ void main() {
     });
     test('removeWhere', () {
       final list = _sortedList;
-      list.removeWhere((it) => it % 2 == 0);
+      list.removeWhere((it) => it.isEven);
       expect(list, [1, 3]);
     });
     test('replaceRange', () {
@@ -221,7 +221,7 @@ void main() {
     });
     test('retainWhere', () {
       final list = _sortedList;
-      list.retainWhere((it) => it % 2 == 0);
+      list.retainWhere((it) => it.isEven);
       expect(list, [2, 4]);
     });
     test('reversed', () {