Yup, you should be able to access it from anywhere.
Big apologies, I made some very dumb mistakes on both of these suggestions. I'll update my previous posts.
First, I had the context for the relative path {[.].path} wrong. This would actually return the path of the parent folder, not the path of your expression tag.
Second, I had the syntax wrong for the this keyword. Correct syntax is {this.path}.
Below are example outputs for {[.].path} and {this.path}:
Does {this.path} solve your original issue?