Abstract Web Machine

[johnjbarton]

One of the areas where we have good potential for collaborative work
and cross-browser implementation is in an API for describing the web
runtime. The idea is to have a description of the runtime independent
of its implementation. The W3C standards already define most of the
runtime API in a (more-or-less) browser-independent way. We just need
to complete the job to include things such as stack frames and
windows. The API needs to be extensible and accommodate variations in
implementation and depth of implementation (supported features varying
across browsers).

Maybe such a thing already exists?

jjb

[Mike Collins]

I like the name you've chosen for this. I don't know of any standard for things like stack frames, but I'm sure everybody has 'em and I'm willing to bet they look close enough that some kind of common denominator can be found.

You also mention windows, which I think is a good place to start if you like the top-down or outside-in approach.  Firebug has the concept of "contexts", which sort of represent a window, but I believe in cases with things like iframes you have multiple windows. 

The w3c draft spec on the window object defines a "browsing context" which can also be a sequence of documents [ http://www.w3.org/TR/Window/#dfn-browsing-context ].

Do we to attempt to allow debugging across multiple pages? I don't know if any tools currently do this, so do we just assume a 1-to-1 mapping of window to context?  What about js environments without a Window? Do we even care about that case?

I like the idea of an "Abstract Web Machine" because I think to be once we have a wire and data format, we still need to have a clear idea of precisely what it is that we are attempting to debug, and right now that may differ from browser to browser.

mc