Environment variable, referencing another environment variable

Question

I found, that Rapid Environment Editor program, displays some variables as of type "expandable string". Such variables can refer another variables, for example

JAVA_HOME_45 = ...
JAVA_HOME = %JAVA_HOME_45%
PATH = %JAVA_HOME%\bin

The problem is that such variables are not working from time to time.

The question is: at which level are they implemented? Is this Windows feature? If yes, then how to activate/deactivate/debug it?

Answer 1

I just tested it and it works (like JimHawkins said) with the standard environment variables editor.

This means that it is a Windows feature and it should always be turned on.

You can "debug" it if you open a Console and enter: echo %PATH%.