[EuroPython] help requested with mozilla dev team: pyjamas-desktop (python-xpcom) blocked by JS advocates

Luke Kenneth Casson Leighton luke.leighton at googlemail.com
Sat Jul 4 16:59:20 CEST 2009

folks, hi, at the europython sprint, i made this patch to 2D Canvas in
xulrunner today:

the background is that this is the last piece of the puzzle so that
pyjamas-desktop's examples can all work, properly.  the last piece is
getting SVG 2D Canvas to be accessible so that you can use python to
write SVG 2D Canvas desktop applications.

basically, i encountered an issue - a design flaw - in the python
bindings (with optional arguments).  the flaw - the assumption - is
that the functions will always be called from javascript, and so the
function call arguments (which can in javascript be of arbitrary
length) are all accessible inside XUL.

by patching XUL, i've made it possible for python-xpcom to gain access
to the three most popular (and necessary) arguments of drawImage.

already as you can see, one of the mozilla developers has made it
clear that he believes that, although the patch may be necessary for
pyjamas-desktop and necessary for all python-xpcom applications, they
just don't care: Javascript is all that they care about.

this would be a bad precedent to let the mozilla developers get away
with such arbitrary decision-making, which, taken at face value,
basically turns mozilla into a closed proprietary platform.

please therefore can i ask people to register on bugzilla.mozilla.org
and voice their concerns on the bugreport in some way, so that the
python-xpcom technology not be left out, here, by arbitrary and
"closed shop" decision making.

if you do not voice your concerns, and the patch is not accepted, then
you will need to patch xulrunner yourselves in order to utilise python
bindings to SVG 2D Canvas, which, i am sure, you would find much more
burdensome than just being able to install pre-compiled packages as
provided direct from the mozilla dev team.

many thanks,


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