Gain insights into Dart's object-oriented features, explore extensions, enums, mixins, and asynchronous programming. Discover hands-on code practice to confidently apply Dart in your projects.

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dart2_7

Dart is a fully object-oriented, class-based, simple, and clean language. Google’s popular mobile framework, Flutter uses Dart language to implement high-quality native applications, so it’s recommended that you understand Flutter before beginning this course.

In this course, you will dive deep into Dart 2 language features while using interactive hands-on code playgrounds. This course will help you become confident with Dart extensions, enums, mixins, generics, libraries, asynchronous programming, class variables, callable classes, and generator functions.

By the end of this course, you will have a strong understanding of Dart principles, and you’ll be ready to start using this powerful language in your own projects.

Developing Web Applications with Dart

# Introduction

In Dart, functions are objects too. It is an object of type [`Function`](https://api.dart.dev/stable/2.8.4/dart-core/Function-class.html). Similar to other objects, functions can be passed as arguments to other functions and can be assigned to variables as well.

A callable class allows its instance to be called as a function. This feature of the Dart language is useful for making named-functions.


# Implementing a callable Class

All Dart functions have a `call` method. To make a class ***Callable***, the `call()` method needs to be implemented. Let's declare a callable class below:

```dart
class Addition {
  int call(int a, int b) => a + b;
}
```

The above class' `call` method takes two arguments and returns their sum.


# Using a callable Class

Let's check out using the `Addition` callable class in the code below. The `addition` object is of the `Addition` type. Now, `addition(1, 2)` can be called to calculate the sum of the given numbers.


In this lesson, you will learn about the callable class.

Introduction

Dart Extensions

Dart Enums

Dart Mixins

Dart Generics

Dart Libraries

Asynchronous Programming In Dart

Miscellaneous

Next Steps

Callable Class

Introduction