[Haskell-cafe] Draft chapters of "Real World Haskell" now publicly available

[Wolfgang Jeltsch]

Am Donnerstag, 7. Februar 2008 18:33 schrieben Sie:
> Interesting. Thanks for the reply.
>
> It might be nice to have some performance benchmarks for all these
> experimental systems, so we can compare them.

I think, the most important thing is the asymptotical time behavior, e.g., 
whether the time of a certain task is linear, logarithmic or constant in the 
number of widgets.  Constant factors can always be improved.  So performance 
benchmarks don’t seem so important to me in the current early state of FRP 
GUI libraries.

> I could understand that performance might be an issue for games, but for
> GUIs? I mean many imperative GUI systems use rather slow message
> dispatching systems, and we use those every day. Look at the new Windows
> Presentation Foundation system found in VISTA. Here events are broadcasted
> and routed through the whole element tree. This is also rather slow I
> guess.

Are they rooted through every node of the tree (linear time) or are they 
routed down the tree to a leaf (not more than logarithmic time, probably).  
The latter would be acceptable, the former not.  The problem I noted on the 
Grapefruit talk page might result in a Yampa-based GUI taking linear time for 
handling a single event (but I’m not completely sure about that).

Does Vista’s event handling really have linear behavior as your statement 
seems to suggest?

Best wishes,
Wolfgang