Hello Antonio, And what are the rough time-estimates?
Thank you, -Yury On 2011-09-12, at 9:49 AM, Antonio Cuni wrote: > Hello pypy-dev, > > in the past weeks, I and the other core developers have talked a lot about > supporting Python 3 in PyPy. The task is huge and it's unlikely that it will > be completed shortly based only on volunteer work, so we came up with the > following proposal, which splits the work into several steps and sub-steps, > togheter with an estimate of how much money is needed to complete each one. > > The plan is to publish the proposal on the blog, and publicly ask for > donations, with the hope to collect enough to cover the whole work. However, > before putting it on the blog we would like to ask for your comments/thoughts > about it. Any feedback will be appreciated! > > Thank you, > Antonio (on the behalf of the PyPy team) > > > Python 3 on PyPy > ================= > > The release of Python 3 has been a major undertaking for the Python community, > both technically and socially. So far PyPy implements only the version 2 of > the Python language, which creates a very dangerous potential for a community > split. We believe that by supporting both versions of the language we will > help to fill the gap. > > This project should help both the part of the Python community which is > reluctant to use PyPy because it does not support Python 3, and the part which > is reluctant to move to Python 3 because they are already PyPy users. > > However, porting PyPy to Python 3 requires a lot of work, and it will take a > long time before we can complete it by relying only on volunteer work. Thus, > we are asking the community to help with funding the necessary work, to make > it happen faster. > > High level description > ----------------------- > > The goal of this project is to write an interpreter that interprets version > 3 of Python language. To be precise we would aim at having Python 3.2 > interpreter together in the same codebase as python 2.7 one. > > At the end of the project, it will be possible to decide at translation time > whether to build an interpreter which supports Python 2.7 or Python 3.2 and > both versions will be nightly tested and available from nightly builds. > > The focus of this project is on compatibility, not performance. In > particular, it might be possible that the resulting Python 3 interpreter will > be slower than the Python 2 one. If needed, optimizing and making it more JIT > friendly will be the scope of a separate project. > > Step 1: core language > ---------------------- > > In this step, we implement all the changes to the core language, > i.e. everything which is not in the extension modules. This includes, but it > is not necessarily limited to the following items, which are split into two > big areas: > > * **Sub-step 1.1**: string vs unicode and I/O: > > - adapt the existing testing infrastructure to support running Python 3 > code > > - string vs bytes: the interpreter uses unicode strings everywhere. > > - the ``print`` function > > - ``open`` is now an alias for ``io.open``, removal of the old file type. > > - string formatting (for the part which is not already implemented in > Python > 2.7) > > - the _io module (for the part which is not already implemented in Python > 2.7) > > - syntactic changes to make ``io.py`` importable (in particular: > ``metaclass=...`` in class declarations) > > - **Estimate cost**: 35.000 $ > > * **Sub-step 1.2**: other syntactic changes, builtin types and functions, > exceptions: > > - views and iterators instead of lists (e.g., ``dict.items()``, ``map``, > ``range`` & co.) > > - new rules for ordering comparisons > > - removal of old-style classes > > - int/long unification > > - function annotations > > - smaller syntax changes, such as keyword-only arguments, ``nonlocal``, > extended iterable unpacking, set literals, dict and set comprehension, > etc. > > - changes to exceptions: ``__traceback__`` attribute, chained exceptions, > ``del e`` at the end of the except block, etc. > > - changes to builtins: ``super``, ``input``, ``next()``, etc. > > - improved ``with`` statement > > - **Estimate cost**: 25.000 $ > > > Note that the distinction between sub-steps 1.1 and 1.2 is blur, and it might > be > possible that during the development we will decide to move items between the > two sub-steps, as needed. > > For more information, look at the various "What's new" documents: > > - http://docs.python.org/py3k/whatsnew/3.0.html > > - http://docs.python.org/py3k/whatsnew/3.1.html > > - http://docs.python.org/py3k/whatsnew/3.2.html > > **Total estimate cost**: 60.000 $ > > > Step 2: extension modules > -------------------------- > > In this step, we implement all the changes to the extension modules which are > written in C in CPython. This includes, but it is not necessarily limited to: > > - ``collections``, ``gzip``, ``bz2``, ``decimal``, ``itertools``, ``re``, > ``functools``, ``pickle``, ``_elementtree``, ``math``, etc. > > **Estimate cost**: this is hard to do at this point, we will be able to give a > more precise estimate as soon as Step 1 is completed. As a reference, it > should be possible to complete it with 35.000 $ > > Step 3: cpyext > -------------- > > The ``cpyext`` module allows to load CPython C extensions in PyPy. Since the > C API changed a lot between Python 2.7 and Python 3.2, ``cpyext`` will not > work out of the box in the Python 3 PyPy interpreter. In this step, we will > adapt it to work with Python 3 as well. > > Note that, even for Python 2, ``cpyext`` is still in a beta state. In > particular, not all extension modules compile and load correctly. As a > consequence, the same will be true for Python 3 as well. As a general rule, > we expect that if a Python 2 module works with ``cpyext``, the corresponding > Python 3 version will also work when this step is completed, although the > details might vary depending on the exact C extension module. > > **Estimate cost**: 10.000 $ > > _______________________________________________ > pypy-dev mailing list > pypy-dev@python.org > http://mail.python.org/mailman/listinfo/pypy-dev _______________________________________________ pypy-dev mailing list pypy-dev@python.org http://mail.python.org/mailman/listinfo/pypy-dev
