I am a bit new to Pharo, anyone please correct me if I am wrong.
excellent initiative. Explaining is an excellent way to learn.
The Workspace has a #mustDeclareVariables: method. I am assuming it is set to false by default. The colour changes once you DoIt on the code, as the variable is automatically created and bound to the workspace, so after running once, it exists. You can see this as the first time when you try inspect a variable, an error occurs. After DoIt, it changes colour, and you can inspect it. Cheers, -Edward
