title: How to describe file structure?
body: <p>At the current point of time, I am modeling the project and I have a really serious question: how to describe the structure of the file(archive)?</p>
  
  <p>What I mean: in this project, we will have our custom file extension, let's call it "anlib", it will be a rar archive with a pre-defined structure like jar.</p>
  
  <p>But how to describe it in UML? Neither component diagram nor deployment diagram support aggregation or composition.</p>