At my one client we use the Ext javascript library, which is somewhat of an all-singing-all-dancing javascript library with dozens of compound widgets, particularly these huge, heavily abstracted searchable, sortable, selectable grid widgets.  Ext doesn't float my boat.  I wouldn't pick it up to use it on a personal project.  The API just seems so large that I feel I have to look up every call and method.  The fact that it seems to take half a minute to load all the grids and widgets you get on a heavily-ext-ified page doesn't thrill me either.

Tonight I got a chance to sit down and use Mochikit with TurboGears (and Kid).  I implemented a simple live-search page (that is, search a database for the intersection of values which match a set of per-field search values) in about 150 lines of html, javascript and Python.  No big deal, but what made me enjoy it (to the point that I've now spent far more (almost 4 hours now) than the original 15 minutes I'd planned for the spike test) was that it seemed so logical and small, just a small collection of very sharp tools you can use to make Javascript feel more Pythonic.

I like the deferred model (a-la Twisted), and it's there.  I like the signal-slot mechanism (a-la Qt or Pydispatcher), and it's there.  I like functional programming (a-la map, and friends) and it's there.  Even the programmattic creation of html is pretty sweet (nevow's stan inspired).  Basically the code looks just about how I would expect the code to look, short, concise, but readable and easily maintained.

After half an hour with the library I was writing most of my code without reference to the documentation.  About the only thing that really tripped me up was that the signal-based code for onload needs to be bound to the *window* in order to work... rookie mistake I suppose.  That small-enough-to-fit-in-your-mind and regular-enough-to-predict-what-will-be pattern is IMO extremely Pythonic.

One last thought.  Am I the only one who finds that kid/genshi is best exploited by passing model objects directly to the view?  I know, I know, the controller should resolve everything to low-level values before invoking the view... but it's *so* nice to be able to use SQLAlchemy/Elixir bindings to traverse the objects and use common function definitions to provide a consistent view of the objects wherever they show up...  being able to say "conference.owner.company.name" to display the value is just so convenient... even if it does wind up embedding code in the view.