Packages enable the creation of modular code that can be shared easily. The simplest package should at least contain the following:
- A pubspec.yaml file, with the package name, version, and other metadata
- A lib folder, containing the code of the package
A package can contain more than a single file in the lib folder, but must contain at least a single dart file with the name of the package; in our example, area.dart.
The area.dart file contains two methods, one to calculate the area of a rectangle, and the second to calculate the area of a triangle. It would make sense to have a single method that calculates both, but we need two methods for part 2 of this recipe, which follows.
In the pubspec.yaml file, we import the intl package:
intl: ^0.17.0
One of the great features of packages is that when you add a dependency there, and you depend on a package, you don't need to depend on that package from the main app. That means you do not have to import intl into...