Levels of abstraction

Here's a concept that crystallized for me today: a programming system that could present code at different levels of abstraction at the same time. Well - clearly not at the same time, but ... a system that had something like a semantic organization of the code could present it at a higher level for a summary view, then get more specific as needed.

This is again something like literate programming, but closer to the code. It would identify larger structures within the source code as having a meaningful relationship with one other, without obscuring the specific source code.

A Lisp macro system is great at producing levels of abstraction, and in many cases this is exactly what's needed; I don't care where the compiler puts variables, so I don't need that low level. But when approaching a large software system, I need to understand what parts of it correspond to specific features, and only look at the features I'm working with at the moment.

Or something. I need to refine this further. But here's kind of where I want to go with this. I've got a venture going with wxPerl, and so I'm developing it in Wx::Declarative (at least as far as I can). I'd like to be able to have a summary description of the overall application, while still having full access to the lower-level specifications of the different panels and so on. I'm not sure I want to put things into a different file, because it's all so compact that I like the idea of having it all in one place (with "business logic" put into a separate module, but with the presentation all being in one place).

Semantically, it would be nice to be able to integrate this summary structure into the structure of the code. I'm really not sure what that would look like, though.