PyPy Sprint announcement & news from the project ================================================ We are coming close to a first experimental release of PyPy, a more flexible Python implementation written in Python. The sprint to make this happen will take place in Amsterdam, a city know to be reachable by cheap flights :-) This is 1) the announcement for the sprint; 2) news about the current state of PyPy; 3) some words about a proposal we recently submitted to the European Union. Amsterdam Sprint Details ------------------------ The Sprint will take place from the 14th of December to the 21st of December at the "Vrije Universiteit in Amsterdam", 14th-21th Dec 2003. thanks to Etienne Posthumus, who helps us to organize the event. The main goal will be a complete C translation of PyPy, probably still using a hacked Pyrex-variant as an intermediate layer and using CPython's runtime. We also plan to work on some fun frontends to PyPy like one based on pygame or a web browser to visualize interactions between interpreter and objectspace. If you want to participate on the sprint, please subscribe here http://codespeak.net/mailman/listinfo/pypy-sprint and list yourself on this wiki page http://codespeak.net/moin/pypy/moin.cgi/AmsterdamSprint where you will also find more information as the sprint date approaches. If you are just interested but don't know if you come then only subscribe to the mailing list. State of the PyPy project -------------------------- PyPy works pretty well but still on top of CPython. The double interpretation penalty makes it - as expected - incredibly slow :-) In the Berlin sprint we have thus started to work on the "translation" part, i.e. how this code should be translated into C. We can now translate simple functions to C-like code including some type annotations. For convenience, we are reusing a modified subset of Pyrex to generate the low-level C code. Thanks to Seo (who joined the project from south-korea) we also have a lisp-backend to fuel the endless c.l.py threads about python versus lisp :-) The goal of the next sprint is to complete this work so that we can translate the complete PyPy source into a huge Pyrex module, and then a big CPython extension module. True, the result is not independent from CPython, as it runs reusing its runtime environment. But it's probably an interesting enough state to make a public release from. The translation is done by generating a control flow of functions by means of abstract interpretation. IOW, we run the PyPy interpreter with a custom object space ("flowobjspace") which generates a control flow graph (including the elementary operations) which is then used to generate low-level code for backends. We also have preliminary type inference on the graphs, which can be used by the Pyrex generator to emit some C type declarations. Writing transformations and analysis of these graphs and displaying them with GraphViz's 'dot' is great fun! We certainly have a greater need than ever for graphical interactive tools to see, understand and debug all these graph manipulations and run tests of them. Currently it is a bit difficult to write a test that checks that a transformed graph "looks right"! What we expect from the Amsterdam sprint is thus: - a big not-too-slow "cpypy.so" extension module for CPython, where at least integer arithmetic is done efficiently - interactive tools to display and debug and test PyPy, visualizing control flow, call-graphs and state models. - improving and rewriting our testing tools to give us more control over the testing process, and to allow more interactive testing sessions. Other interesting News ---------------------- Before mid October, we also had a quite different Sprint. It was an approximately 10-day effort towards submitting a proposal to the EU. If it is accepted we will have resources to fund some developers working full- or parttime on the project. However, our "sprint driven development" will continue to play the central role for development of PyPy. There are especially two technical sections of the proposal which you might find interesting to read: "Scientific and technological objectives": http://codespeak.net/pypy/index.cgi?doc/funding/B1.0 "Detailed implementation plan" http://codespeak.net/pypy/index.cgi?doc/funding/B6.0 Maybe you want to read the whole proposal for other reasons, too, like making a EU project of your own or competing with us. Actually, with our sprints there is usually a lot of room for cooperation :-) Anyway, here is the PDF-url: http://codespeak.net/svn/pypy/trunk/doc/funding/proposal/part_b.pdf Everybody who thinks that he/she could help on the project is invited to join! Btw, the latest discussions about our sprint goals usually take place on the pypy-dev list: http://codespeak.net/mailman/listinfo/pypy-dev have fun, Armin & Holger