Hello World in Dart

Welcome to the Hello World in Dart page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

void main() => print('Hello, World!');

Hello World in Dart was written by:

• Jeremy Grifski

This article was written by:

• Jeremy Grifski
• rzuckerm

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

Coming from a Java background, the following snippet of code is downright stripped to the barebones.

In order to implement Hello World in Dart, developers need to understand only three concepts like main methods, strings, and arrow functions. But look at the code above, it seems deceptively easy, right?

What is going on is main() only does one thing, print the phrase "Hello, World!". We'll dig into how and why all of this happens in a bit, but it's important to step away for a bit and just look at what's there and acknowledge how simple it is.

In a Dart project, only one class would have a main method (main()). A main method is how every Dart program knows where to start. Therefore, every program must have exactly one of these main methods implemented. Don't worry too much about the syntax. Just know that we need a main method.

Then we have to output our greeting ("Hello, World!") to the command line. To do so, we have to leverage a static method out of Dart's built-in library. It's the print statement. It's a method like main() only difference is we put a string inside the parentheses. It tells the computer to take the string and print out so we can read it.

The last concept are arrow functions (=>). These are methods like print or, in this case, main that only do one thing. Because they only do one thing, we can use => from the method's definition (main()) directly to the logic. Other more complex methods may require the use of return. But that's not required in this case.

How to Run the Solution

To run this program, just download the Dart interpreter. Then, run this:

dart hello-world.dart

Alternatively, you can use an online Dart interpreter.