Why can't I install this aqueduct

Question

Why can't I install this aqueduct?

Although I have installed dart before as shown in the picture:

Answer 1

It's important to ensure that the dart SDK is in the PATH. You can easily test it by trying to use pub or dart.

One way to ensure it's in the PATH is by creating a .bashrc file in your user's folder.

Then add the following:

export PATH="$PATH:/path/to/dart/installation/bin/folder"

Answer 2

First of all check if dart is installed using dart --version if it gives a command not found error that means it is not installed (hence why you cannot install aqueduct since it requires pub which is shipped with the dart sdk). To install dart on macOS first install brew and the follow the instruction here https://dart.dev/get-dart (don't run brew switch dart 2.1.0 as shown in the screenshot since it makes no sense because current the latest stable is 2.9.1 and 2.1.0 is pretty old).

If you don't want to install brew you can download the sdk here (for your system) extract it, and update your path variable as @gabriel-octávio says.