Printing Output

print writes one value and ends the line.

Example

void main() {
  print('Hello');
  print(42);
  print(3.5);
  print(true);
  print([1, 2, 3]);
  print({'a': 1, 'b': 2});
  print(null);
  print('A' + 'B');
}

Expected output

Hello
42
3.5
true
[1, 2, 3]
{a: 1, b: 2}
null
AB

print takes one argument. To print several values on a line, build a single string with interpolation (covered in the Strings lesson):

void main() {
  final city = 'Oslo';
  final temp = 21;
  print('$city: $temp°C');
}

Oslo: 21°C

To print without a new line in a command-line program, use stdout.write(...) from dart:io:

import 'dart:io';

void main() {
  stdout.write('Loading...');
  print('done');
}

Loading...done

Practice

Print your city and today's temperature on one line, like Lagos: 30°C, using interpolation.

void main() {
  final city = 'Lagos';
  final temperature = 30;
  print('$city: $temperature°C');
}