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Create dart-ru.html.markdown
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ru-ru/dart-ru.html.markdown
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@ -0,0 +1,727 @@
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---
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language: dart
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filename: learndart-ru.dart
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contributors:
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- ["Joao Pedrosa", "https://github.com/jpedrosa/"]
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- ["Vince Ramces Oliveros", "https://github.com/ram231"]
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translators:
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- ["nikaose", "https://github.com/nikaose"]
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lang: ru-ru
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---
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**Dart** это однопоточный язык программирования общего назначения.
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Он многое заимствует из других основных языков.
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Он поддерживает потоки, фьючерсы (известные как промисы в JavaScript), дженерики, первоклассные функции (замыкания) и проверку статического типа.
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Dart может работать на любой платформе, включая веб-интерфейс, интерфейс командной строки, десктопные, мобильные устройства и устройства IoT.
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Самая спорная функция Dart это ~~Необязательный ввод~~ Статическая безопасность типов и [Проверка звукового типа](https://dart.dev/guides/language/sound-dart).
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```dart
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import "dart:collection";
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import "dart:math" as math;
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/// Добро пожаловать в «Изучите Dart за 15 минут». http://dart.dev/
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/// Это исполняемый учебник. Вы можете запустить его с помощью Dart или
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/// Попробуйте Dart! если вы скопируете/вставите его сюда: http://dartpad.dev/
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/// Вы также можете запустить Flutter в DartPad, щелкнув `< > New Pad ` и выбрав Flutter.
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/// В Dart все является объектом.
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/// Каждое объявление объекта является экземпляром Null и
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/// Null также является объектом.
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/// 3 типа комментариев в Dart
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// Однострочный комментарий
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/**
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* Многострочный комментарий
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* Можно прокомментировать несколько строк
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*/
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/// Комментарий к документации кода
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/// Он использует синтаксис markdown для создания документации кода при создании API.
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/// Комментарий к документации кода — рекомендуемый выбор при документировании API, классов и методов.
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/// 4 типа объявления переменных.
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/// Константы — это переменные, которые являются неизменяемыми и не могут быть изменены.
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/// `const` в Dart должен использовать объявление имени SCREAMING_SNAKE_CASE.
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const CONSTANT_VALUE = "I CANNOT CHANGE";
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CONSTANT_VALUE = "DID I?"; //Error
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/// Final is another variable declaration that cannot be change once it has been instantiated. Commonly used in classes and functions
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/// `final` can be declared in pascalCase.
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final finalValue = "value cannot be changed once instantiated";
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finalValue = "Seems not"; //Error
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/// `var` is another variable declaration that is mutable and can change its value. Dart will infer types and will not change its data type
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var mutableValue = "Variable string";
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mutableValue = "this is valid";
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mutableValue = false; // Error.
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/// `dynamic` is another variable declaration in which the type is not evaluated by the dart static type checking.
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/// It can change its value and data type.
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/// Some dartisans uses dynamic cautiously as it cannot keep track of its data type. so use it at your own risk
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dynamic dynamicValue = "I'm a string";
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dynamicValue = false; // false
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/// Functions can be declared in a global space
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/// Function declaration and method declaration look the same. Function
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/// declarations can be nested. The declaration takes the form of
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/// name() {} or name() => singleLineExpression;
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/// The fat arrow function declaration can be an implicit or
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/// explicit return for the result of the expression.
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/// Dart will execute a function called `main()` anywhere in the dart project.
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///
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example1() {
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nested1() {
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nested2() => print("Example1 nested 1 nested 2");
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nested2();
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}
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nested1();
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}
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/// Anonymous functions don't include a name
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example2() {
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//// Explicit return type.
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nested1(void Function() fn) {
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fn();
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}
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nested1(() => print("Example2 nested 1"));
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}
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/// When a function parameter is declared, the declaration can include the
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/// number of parameters the function takes by explicitly specifying the names of the
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/// parameters it takes.
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example3() {
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planA(fn(String informSomething)) {
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fn("Example3 plan A");
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}
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planB(fn) {
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// Or don't declare number of parameters.
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fn("Example3 plan B");
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}
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planA((s) => print(s));
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planB((s) => print(s));
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}
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/// Functions have closure access to outer variables.
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/// Dart will infer types when the variable has a value of something.
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/// In this example dart knows that this variable is a String.
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var example4Something = "Example4 nested 1";
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example4() {
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nested1(fn(informSomething)) {
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fn(example4Something);
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}
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nested1((s) => print(s));
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}
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/// Class declaration with a sayIt method, which also has closure access
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/// to the outer variable as though it were a function as seen before.
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var example5method = "Example5 sayIt";
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class Example5Class {
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sayIt() {
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print(example5method);
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}
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}
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example5() {
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/// Create an anonymous instance of the Example5Class and call the sayIt
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/// method on it.
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/// the `new` keyword is optional in Dart.
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new Example5Class().sayIt();
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}
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/// Class declaration takes the form of class name { [classBody] }.
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/// Where classBody can include instance methods and variables, but also
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/// class methods and variables.
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class Example6Class {
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var instanceVariable = "Example6 instance variable";
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sayIt() {
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print(instanceVariable);
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}
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}
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example6() {
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Example6Class().sayIt();
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}
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/// Class methods and variables are declared with "static" terms.
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class Example7Class {
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static var classVariable = "Example7 class variable";
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static sayItFromClass() {
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print(classVariable);
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}
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sayItFromInstance() {
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print(classVariable);
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}
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}
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example7() {
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Example7Class.sayItFromClass();
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new Example7Class().sayItFromInstance();
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}
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/// Dart supports Generics.
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/// Generics refers to the technique of writing the code for a class
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/// without specifying the data type(s) that the class works on.
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/// Source: https://stackoverflow.com/questions/4560890/what-are-generics-in-c
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/// Type `T` refers to any type that has been instantiated
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/// you can call whatever you want
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/// Programmers uses the convention in the following
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/// T - Type(used for class and primitype types)
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/// E - Element(used for List, Set, or Iterable)
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/// K,V - Key Value(used for Map)
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class GenericExample<T>{
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void printType(){
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print("$T")
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}
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// methods can also have generics
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genericMethod<M>(){
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print("class:$T, method: $M");
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}
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}
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/// List are similar to arrays but list is a child of Iterable<E>
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/// Therefore Maps, List, LinkedList are all child of Iterable<E> to be able to loop using the keyword `for`
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/// Important things to remember:
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/// () - Iterable<E>
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/// [] - List<E>
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/// {} - Map<K,V>
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/// List are great, but there's a restriction for what List can be
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/// outside of function/method bodies. List on the outer scope of class
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/// or outside of class have to be constant. Strings and numbers are constant
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/// by default. But arrays and maps are not. They can be made constant by
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/// declaring them "const". Kind of similar to Javascript's Object.freeze()
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const example8List = ["Example8 const array"];
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const example8Map = {"someKey": "Example8 const map"};
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/// Declare List or Maps as Objects.
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List<String> explicitList = new List<String>();
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Map<String,dynamic> explicitMaps = new Map<String,dynamic>();
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explicitList.add("SomeArray");
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example8() {
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print(example8Map["someKey"]);
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print(explicitList[0]);
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}
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/// Assigning a list from one variable to another will not be the same result.
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/// Because dart is pass-reference-by-value.
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/// So when you assign an existing list to a new variable.
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/// Instead of List, it becomes an Iterable
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var iterableExplicitList = explicitList;
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print(iterableExplicitList) // ("SomeArray"); "[]" becomes "()"
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var newExplicitLists = explicitList.toList() // Converts Iterable<E> to List<E>
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/// Loops in Dart take the form of standard for () {} or while () {} loops,
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/// slightly more modern for (.. in ..) {}, or functional callbacks with many
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/// supported features, starting with forEach,map and where.
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var example9Array = const ["a", "b"];
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example9() {
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for (int i = 0; i < example9Array.length; i++) {
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print("Example9 for loop '${example9Array[i]}'");
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}
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var i = 0;
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while (i < example9Array.length) {
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print("Example9 while loop '${example9Array[i]}'");
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i++;
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}
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for (final e in example9Array) {
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print("Example9 for-in loop '${e}'");
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}
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example9Array.forEach((e) => print("Example9 forEach loop '${e}'"));
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}
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/// To loop over the characters of a string or to extract a substring.
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var example10String = "ab";
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example10() {
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for (var i = 0; i < example10String.length; i++) {
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print("Example10 String character loop '${example10String[i]}'");
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}
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for (var i = 0; i < example10String.length; i++) {
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print("Example10 substring loop '${example10String.substring(i, i + 1)}'");
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}
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}
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/// `int`, `double` and `num` are the three supported number formats.
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/// `num` can be either `int` or `double`.
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/// `int` and `double` are children of type `num`
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example11() {
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var i = 1 + 320, d = 3.2 + 0.01;
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final num myFinalNumDouble = 2.2;
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final num myFinalNumInt = 2;
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final int myFinalInt = 1;
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final double myFinalDouble = 0.1;
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num myNumDouble = 2.2;
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num myNumInt = 2;
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int myInt = 1;
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double myDouble = 0; // Dart will add decimal prefix, becomes 0.0;
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myNumDouble = myFinalInt; // valid
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myNumDouble = myFinalDouble; // valid
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myNumDouble = myFinalNumInt; // valid
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myNumInt = myFinalInt; // valid
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myNumInt = myFinalDouble; // valid
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myNumInt = myFinalNumDouble; // valid
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myInt = myNumDouble; // error
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myInt = myFinalDouble; // error
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myInt = myFinalNumInt; // valid
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myDouble = myFinalInt; // error
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myDouble = myFinalNumInt; // error
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myDouble = myFinalNumDouble; // valid
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print("Example11 int ${i}");
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print("Example11 double ${d}");
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}
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/// DateTime provides date/time arithmetic.
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example12() {
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var now = new DateTime.now();
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print("Example12 now '${now}'");
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now = now.add(new Duration(days: 1));
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print("Example12 tomorrow '${now}'");
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}
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/// Regular expressions are supported.
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example13() {
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var s1 = "some string", s2 = "some", re = new RegExp("^s.+?g\$");
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match(s) {
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if (re.hasMatch(s)) {
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print("Example13 regexp matches '${s}'");
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} else {
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print("Example13 regexp doesn't match '${s}'");
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}
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}
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match(s1);
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match(s2);
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}
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/// Boolean expressions support implicit conversions and dynamic type
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example14() {
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var a = true;
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if (a) {
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print("true, a is $a");
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}
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a = false;
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if (a) {
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print("true, a is $a");
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} else {
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print("false, a is $a"); /// runs here
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}
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/// dynamic typed null can not be convert to bool
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var b; /// b is dynamic type
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b = "abc";
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try {
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if (b) {
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print("true, b is $b");
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} else {
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print("false, b is $b");
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}
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} catch (e) {
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print("error, b is $b"); /// this could be run but got error
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}
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b = null;
|
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if (b) { /// Failed assertion: boolean expression must not be null)
|
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print("true, b is $b");
|
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} else {
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print("false, b is $b");
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}
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/// statically typed null can not be convert to bool
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var c = "abc";
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c = null;
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/// compilation failed
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/// if (c) {
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/// print("true, c is $c");
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/// } else {
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/// print("false, c is $c");
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/// }
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}
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/// try/catch/finally and throw are used for exception handling.
|
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/// throw takes any object as parameter;
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example15() {
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try {
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try {
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throw "Some unexpected error.";
|
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} catch (e) {
|
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print("Example15 an exception: '${e}'");
|
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throw e; /// Re-throw
|
||||
}
|
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} catch (e) {
|
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print("Example15 catch exception being re-thrown: '${e}'");
|
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} finally {
|
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print("Example15 Still run finally");
|
||||
}
|
||||
}
|
||||
|
||||
/// To be efficient when creating a long string dynamically, use
|
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/// StringBuffer. Or you could join a string array.
|
||||
example16() {
|
||||
var sb = new StringBuffer(), a = ["a", "b", "c", "d"], e;
|
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for (e in a) {
|
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sb.write(e);
|
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}
|
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print("Example16 dynamic string created with "
|
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"StringBuffer '${sb.toString()}'");
|
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print("Example16 join string array '${a.join()}'");
|
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}
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||||
|
||||
/// Strings can be concatenated by just having string List next to
|
||||
/// one another with no further operator needed.
|
||||
|
||||
example17() {
|
||||
print("Example17 "
|
||||
"concatenate "
|
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"strings "
|
||||
"just like that");
|
||||
}
|
||||
|
||||
/// Strings have single-quote or double-quote for delimiters with no
|
||||
/// actual difference between the two. The given flexibility can be good
|
||||
/// to avoid the need to escape content that matches the delimiter being
|
||||
/// used. For example, double-quotes of HTML attributes if the string
|
||||
/// contains HTML content.
|
||||
example18() {
|
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print('Example18 <a href="etc">'
|
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"Don't can't I'm Etc"
|
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'</a>');
|
||||
}
|
||||
|
||||
/// Strings with triple single-quotes or triple double-quotes span
|
||||
/// multiple lines and include line delimiters.
|
||||
example19() {
|
||||
print('''Example19 <a href="etc">
|
||||
Example19 Don't can't I'm Etc
|
||||
Example19 </a>''');
|
||||
}
|
||||
|
||||
/// Strings have the nice interpolation feature with the $ character.
|
||||
/// With $ { [expression] }, the return of the expression is interpolated.
|
||||
/// $ followed by a variable name interpolates the content of that variable.
|
||||
/// $ can be escaped like so \$ to just add it to the string instead.
|
||||
example20() {
|
||||
var s1 = "'\${s}'", s2 = "'\$s'";
|
||||
print("Example20 \$ interpolation ${s1} or $s2 works.");
|
||||
}
|
||||
|
||||
/// Optional types allow for the annotation of APIs and come to the aid of
|
||||
/// IDEs so the IDEs can better refactor, auto-complete and check for
|
||||
/// errors. So far we haven't declared any types and the programs have
|
||||
/// worked just fine. In fact, types are disregarded during runtime.
|
||||
/// Types can even be wrong and the program will still be given the
|
||||
/// benefit of the doubt and be run as though the types didn't matter.
|
||||
/// There's a runtime parameter that checks for type errors which is
|
||||
/// the checked mode, which is said to be useful during development time,
|
||||
/// but which is also slower because of the extra checking and is thus
|
||||
/// avoided during deployment runtime.
|
||||
class Example21 {
|
||||
List<String> _names;
|
||||
Example21() {
|
||||
_names = ["a", "b"];
|
||||
}
|
||||
List<String> get names => _names;
|
||||
set names(List<String> list) {
|
||||
_names = list;
|
||||
}
|
||||
|
||||
int get length => _names.length;
|
||||
void add(String name) {
|
||||
_names.add(name);
|
||||
}
|
||||
}
|
||||
|
||||
void example21() {
|
||||
Example21 o = new Example21();
|
||||
o.add("c");
|
||||
print("Example21 names '${o.names}' and length '${o.length}'");
|
||||
o.names = ["d", "e"];
|
||||
print("Example21 names '${o.names}' and length '${o.length}'");
|
||||
}
|
||||
|
||||
/// Class inheritance takes the form of class name extends AnotherClassName {}.
|
||||
class Example22A {
|
||||
var _name = "Some Name!";
|
||||
get name => _name;
|
||||
}
|
||||
|
||||
class Example22B extends Example22A {}
|
||||
|
||||
example22() {
|
||||
var o = new Example22B();
|
||||
print("Example22 class inheritance '${o.name}'");
|
||||
}
|
||||
|
||||
/// Class mixin is also available, and takes the form of
|
||||
/// class name extends SomeClass with AnotherClassName {}.
|
||||
/// It's necessary to extend some class to be able to mixin another one.
|
||||
/// The template class of mixin cannot at the moment have a constructor.
|
||||
/// Mixin is mostly used to share methods with distant classes, so the
|
||||
/// single inheritance doesn't get in the way of reusable code.
|
||||
/// Mixins follow the "with" statement during the class declaration.
|
||||
class Example23A {}
|
||||
|
||||
class Example23Utils {
|
||||
addTwo(n1, n2) {
|
||||
return n1 + n2;
|
||||
}
|
||||
}
|
||||
|
||||
class Example23B extends Example23A with Example23Utils {
|
||||
addThree(n1, n2, n3) {
|
||||
return addTwo(n1, n2) + n3;
|
||||
}
|
||||
}
|
||||
|
||||
example23() {
|
||||
var o = new Example23B(), r1 = o.addThree(1, 2, 3), r2 = o.addTwo(1, 2);
|
||||
print("Example23 addThree(1, 2, 3) results in '${r1}'");
|
||||
print("Example23 addTwo(1, 2) results in '${r2}'");
|
||||
}
|
||||
|
||||
/// The Class constructor method uses the same name of the class and
|
||||
/// takes the form of SomeClass() : super() {}, where the ": super()"
|
||||
/// part is optional and it's used to delegate constant parameters to the
|
||||
/// super-parent's constructor.
|
||||
class Example24A {
|
||||
var _value;
|
||||
Example24A({value: "someValue"}) {
|
||||
_value = value;
|
||||
}
|
||||
get value => _value;
|
||||
}
|
||||
|
||||
class Example24B extends Example24A {
|
||||
Example24B({value: "someOtherValue"}) : super(value: value);
|
||||
}
|
||||
|
||||
example24() {
|
||||
var o1 = new Example24B(), o2 = new Example24B(value: "evenMore");
|
||||
print("Example24 calling super during constructor '${o1.value}'");
|
||||
print("Example24 calling super during constructor '${o2.value}'");
|
||||
}
|
||||
|
||||
/// There's a shortcut to set constructor parameters in case of simpler classes.
|
||||
/// Just use the this.parameterName prefix and it will set the parameter on
|
||||
/// an instance variable of same name.
|
||||
class Example25 {
|
||||
var value, anotherValue;
|
||||
Example25({this.value, this.anotherValue});
|
||||
}
|
||||
|
||||
example25() {
|
||||
var o = new Example25(value: "a", anotherValue: "b");
|
||||
print("Example25 shortcut for constructor '${o.value}' and "
|
||||
"'${o.anotherValue}'");
|
||||
}
|
||||
|
||||
/// Named parameters are available when declared between {}.
|
||||
/// Parameter order can be optional when declared between {}.
|
||||
/// Parameters can be made optional when declared between [].
|
||||
example26() {
|
||||
var _name, _surname, _email;
|
||||
setConfig1({name, surname}) {
|
||||
_name = name;
|
||||
_surname = surname;
|
||||
}
|
||||
|
||||
setConfig2(name, [surname, email]) {
|
||||
_name = name;
|
||||
_surname = surname;
|
||||
_email = email;
|
||||
}
|
||||
|
||||
setConfig1(surname: "Doe", name: "John");
|
||||
print("Example26 name '${_name}', surname '${_surname}', "
|
||||
"email '${_email}'");
|
||||
setConfig2("Mary", "Jane");
|
||||
print("Example26 name '${_name}', surname '${_surname}', "
|
||||
"email '${_email}'");
|
||||
}
|
||||
|
||||
/// Variables declared with final can only be set once.
|
||||
/// In case of classes, final instance variables can be set via constant
|
||||
/// constructor parameter.
|
||||
class Example27 {
|
||||
final color1, color2;
|
||||
/// A little flexibility to set final instance variables with syntax
|
||||
/// that follows the :
|
||||
Example27({this.color1, color2}) : color2 = color2;
|
||||
}
|
||||
|
||||
example27() {
|
||||
final color = "orange", o = new Example27(color1: "lilac", color2: "white");
|
||||
print("Example27 color is '${color}'");
|
||||
print("Example27 color is '${o.color1}' and '${o.color2}'");
|
||||
}
|
||||
|
||||
/// To import a library, use import "libraryPath" or if it's a core library,
|
||||
/// import "dart:libraryName". There's also the "pub" package management with
|
||||
/// its own convention of import "package:packageName".
|
||||
/// See import "dart:collection"; at the top. Imports must come before
|
||||
/// other code declarations. IterableBase comes from dart:collection.
|
||||
class Example28 extends IterableBase {
|
||||
var names;
|
||||
Example28() {
|
||||
names = ["a", "b"];
|
||||
}
|
||||
get iterator => names.iterator;
|
||||
}
|
||||
|
||||
example28() {
|
||||
var o = new Example28();
|
||||
o.forEach((name) => print("Example28 '${name}'"));
|
||||
}
|
||||
|
||||
/// For control flow we have:
|
||||
/// * standard switch with must break statements
|
||||
/// * if-else if-else and ternary ..?..:.. operator
|
||||
/// * closures and anonymous functions
|
||||
/// * break, continue and return statements
|
||||
example29() {
|
||||
var v = true ? 30 : 60;
|
||||
switch (v) {
|
||||
case 30:
|
||||
print("Example29 switch statement");
|
||||
break;
|
||||
}
|
||||
if (v < 30) {
|
||||
} else if (v > 30) {
|
||||
} else {
|
||||
print("Example29 if-else statement");
|
||||
}
|
||||
callItForMe(fn()) {
|
||||
return fn();
|
||||
}
|
||||
|
||||
rand() {
|
||||
v = new DM.Random().nextInt(50);
|
||||
return v;
|
||||
}
|
||||
|
||||
while (true) {
|
||||
print("Example29 callItForMe(rand) '${callItForMe(rand)}'");
|
||||
if (v != 30) {
|
||||
break;
|
||||
} else {
|
||||
continue;
|
||||
}
|
||||
/// Never gets here.
|
||||
}
|
||||
}
|
||||
|
||||
/// Parse int, convert double to int, or just keep int when dividing numbers
|
||||
/// by using the ~/ operation. Let's play a guess game too.
|
||||
example30() {
|
||||
var gn,
|
||||
tooHigh = false,
|
||||
n,
|
||||
n2 = (2.0).toInt(),
|
||||
top = int.parse("123") ~/ n2,
|
||||
bottom = 0;
|
||||
top = top ~/ 6;
|
||||
gn = new DM.Random().nextInt(top + 1); /// +1 because nextInt top is exclusive
|
||||
print("Example30 Guess a number between 0 and ${top}");
|
||||
guessNumber(i) {
|
||||
if (n == gn) {
|
||||
print("Example30 Guessed right! The number is ${gn}");
|
||||
} else {
|
||||
tooHigh = n > gn;
|
||||
print("Example30 Number ${n} is too "
|
||||
"${tooHigh ? 'high' : 'low'}. Try again");
|
||||
}
|
||||
return n == gn;
|
||||
}
|
||||
|
||||
n = (top - bottom) ~/ 2;
|
||||
while (!guessNumber(n)) {
|
||||
if (tooHigh) {
|
||||
top = n - 1;
|
||||
} else {
|
||||
bottom = n + 1;
|
||||
}
|
||||
n = bottom + ((top - bottom) ~/ 2);
|
||||
}
|
||||
}
|
||||
|
||||
/// Optional Positional Parameter:
|
||||
/// parameter will be disclosed with square bracket [ ] & square bracketed parameter are optional.
|
||||
example31() {
|
||||
findVolume31(int length, int breath, [int height]) {
|
||||
print('length = $length, breath = $breath, height = $height');
|
||||
}
|
||||
|
||||
findVolume31(10,20,30); //valid
|
||||
findVolume31(10,20); //also valid
|
||||
}
|
||||
|
||||
/// Optional Named Parameter:
|
||||
/// parameter will be disclosed with curly bracket { }
|
||||
/// curly bracketed parameter are optional.
|
||||
/// have to use parameter name to assign a value which separated with colan :
|
||||
/// in curly bracketed parameter order does not matter
|
||||
/// these type parameter help us to avoid confusion while passing value for a function which has many parameter.
|
||||
example32() {
|
||||
findVolume32(int length, int breath, {int height}) {
|
||||
print('length = $length, breath = $breath, height = $height');
|
||||
}
|
||||
|
||||
findVolume32(10,20,height:30);//valid & we can see the parameter name is mentioned here.
|
||||
findVolume32(10,20);//also valid
|
||||
}
|
||||
|
||||
/// Optional Default Parameter:
|
||||
/// same like optional named parameter in addition we can assign default value for this parameter.
|
||||
/// which means no value is passed this default value will be taken.
|
||||
example33() {
|
||||
findVolume33(int length, int breath, {int height=10}) {
|
||||
print('length = $length, breath = $breath, height = $height');
|
||||
}
|
||||
|
||||
findVolume33(10,20,height:30);//valid
|
||||
findVolume33(10,20);//valid
|
||||
}
|
||||
|
||||
/// Dart has also added feature such as Null aware operators
|
||||
var isBool = true;
|
||||
var hasString = isBool ?? "default String";
|
||||
|
||||
/// Programs have only one entry point in the main function.
|
||||
/// Nothing is expected to be executed on the outer scope before a program
|
||||
/// starts running with what's in its main function.
|
||||
/// This helps with faster loading and even lazily loading of just what
|
||||
/// the program needs to startup with.
|
||||
main() {
|
||||
print("Learn Dart in 15 minutes!");
|
||||
[
|
||||
example1, example2, example3, example4, example5,
|
||||
example6, example7, example8, example9, example10,
|
||||
example11, example12, example13, example14, example15,
|
||||
example16, example17, example18, example19, example20,
|
||||
example21, example22, example23, example24, example25,
|
||||
example26, example27, example28, example29,
|
||||
example30 // Adding this comment stops the dart formatter from putting all items on a new line
|
||||
].forEach((ef) => ef());
|
||||
}
|
||||
```
|
||||
|
||||
## Further Reading
|
||||
|
||||
Dart has a comprehensive web-site. It covers API reference, tutorials, articles and more, including a
|
||||
useful DartPad (a cloud-based Dart coding playground).
|
||||
[https://dart.dev/](https://dart.dev)
|
||||
[https://dartpad.dev/](https://dartpad.dev)
|
||||
Loading…
Reference in New Issue
Block a user