Author: Wim Lavrijsen <[email protected]> Branch: Changeset: r70908:d426723559fb Date: 2014-04-23 17:15 -0700 http://bitbucket.org/pypy/pypy/changeset/d426723559fb/
Log: doc updates (clarification and a description of nullptr) diff --git a/pypy/doc/cppyy.rst b/pypy/doc/cppyy.rst --- a/pypy/doc/cppyy.rst +++ b/pypy/doc/cppyy.rst @@ -560,6 +560,12 @@ Fixing these bootstrap problems is on the TODO list. The global namespace is ``cppyy.gbl``. +* **NULL**: Is represented as ``cppyy.gbl.nullptr``. + In C++11, the keyword ``nullptr`` is used to represent ``NULL``. + For clarity of intent, it is recommended to use this instead of ``None`` + (or the integer ``0``, which can serve in some cases), as ``None`` is better + understood as ``void`` in C++. + * **operator conversions**: If defined in the C++ class and a python equivalent exists (i.e. all builtin integer and floating point types, as well as ``bool``), it will map onto that python conversion. diff --git a/pypy/doc/extending.rst b/pypy/doc/extending.rst --- a/pypy/doc/extending.rst +++ b/pypy/doc/extending.rst @@ -66,58 +66,26 @@ Reflex ====== -This method is still experimental. It adds the `cppyy`_ module. -The method works by using the `Reflex package`_ to provide reflection -information of the C++ code, which is then used to automatically generate -bindings at runtime. -From a python standpoint, there is no difference between generating bindings -at runtime, or having them "statically" generated and available in scripts -or compiled into extension modules: python classes and functions are always -runtime structures, created when a script or module loads. +The builtin `cppyy`_ module uses reflection information, provided by +`Reflex`_ (which needs to be `installed separately`_), of C/C++ code to +automatically generate bindings at runtime. +In Python, classes and functions are always runtime structures, so when they +are generated matters not for performance. However, if the backend itself is capable of dynamic behavior, it is a much -better functional match to python, allowing tighter integration and more -natural language mappings. -Full details are `available here`_. +better functional match, allowing tighter integration and more natural +language mappings. + +The `cppyy`_ module is written in RPython, thus PyPy's JIT is able to remove +most cross-language call overhead. + +`Full details`_ are `available here`_. .. _`cppyy`: cppyy.html -.. _`reflex-support`: cppyy.html -.. _`Reflex package`: http://root.cern.ch/drupal/content/reflex +.. _`installed separately`: http://cern.ch/wlav/reflex-2013-08-14.tar.bz2 +.. _`Reflex`: http://root.cern.ch/drupal/content/reflex +.. _`Full details`: cppyy.html .. _`available here`: cppyy.html -Pros ----- - -The cppyy module is written in RPython, which makes it possible to keep the -code execution visible to the JIT all the way to the actual point of call into -C++, thus allowing for a very fast interface. -Reflex is currently in use in large software environments in High Energy -Physics (HEP), across many different projects and packages, and its use can be -virtually completely automated in a production environment. -One of its uses in HEP is in providing language bindings for CPython. -Thus, it is possible to use Reflex to have bound code work on both CPython and -on PyPy. -In the medium-term, Reflex will be replaced by `cling`_, which is based on -`llvm`_. -This will affect the backend only; the python-side interface is expected to -remain the same, except that cling adds a lot of dynamic behavior to C++, -enabling further language integration. - -.. _`cling`: http://root.cern.ch/drupal/content/cling -.. _`llvm`: http://llvm.org/ - -Cons ----- - -C++ is a large language, and cppyy is not yet feature-complete. -Still, the experience gained in developing the equivalent bindings for CPython -means that adding missing features is a simple matter of engineering, not a -question of research. -The module is written so that currently missing features should do no harm if -you don't use them, if you do need a particular feature, it may be necessary -to work around it in python or with a C++ helper function. -Although Reflex works on various platforms, the bindings with PyPy have only -been tested on Linux. - RPython Mixed Modules ===================== _______________________________________________ pypy-commit mailing list [email protected] https://mail.python.org/mailman/listinfo/pypy-commit
