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Auto-detection of class memebers wrapped with make_getter()
[SVN r16241]
1 parent a217277 commit f2797ec

8 files changed

Lines changed: 81 additions & 14 deletions

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‎doc/news.html‎

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@@ -29,6 +29,11 @@ <h2 align="center">News/Change Log</h2>
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<hr>
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<dl class="page-index">
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<dt>14 November 2002</dt>
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<dd>Auto-detection of class data members wrapped with <a href=
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"v2/data_members.html#make_getter-spec"><code>make_getter</code></a></dd>
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<dt>13 November 2002</dt>
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<dd>Full Support for <code>std::auto_ptr&lt;&gt;</code> added.</dd>

‎doc/v2/data_members.html‎

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@@ -77,7 +77,15 @@ <h2><a name="functions"></a>Functions</h2>
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<code>C*</code>, and returns the corresponding member <code>D</code>
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member of the <code>C</code> object, converted <code>to_python</code>.
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If <code>policies</code> is supplied, it will be applied to the
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function as described <a href="CallPolicies.html">here</a>.</dt>
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function as described <a href="CallPolicies.html">here</a>. Otherwise,
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the library attempts to determine whether <code>D</code> is a
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user-defined class type, and if so uses <code><a href=
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"return_internal_reference.html#return_internal_reference-spec">return_internal_reference</a>&lt;&gt;</code></dt>
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<dt>for <code>Policies</code>. Note that this test may inappropriately
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choose <code>return_internal_reference&lt;&gt;</code> in some cases
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when <code>D</code> is a smart pointer type. This is a known
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defect.</dt>
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<dt><b>Returns:</b> An instance of <a href=
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"object.html#object-spec">object</a> which holds the new Python
@@ -147,8 +155,8 @@ <h2><a name="examples"></a>Example</h2>
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<p>
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<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
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13 November, 2002
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<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
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13 November, 2002
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<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
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</p>
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<p><i>&copy; Copyright <a href=

‎include/boost/python/converter/builtin_converters.hpp‎

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@@ -38,6 +38,11 @@ namespace detail
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struct builtin_to_python
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{
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static bool convertible() { return true; }
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// This information helps make_getter() decide whether to try to
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// return an internal reference or not. I don't like it much,
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// but it will have to serve for now.
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BOOST_STATIC_CONSTANT(bool, uses_registry = false);
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};
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}
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‎include/boost/python/data_members.hpp‎

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@@ -9,11 +9,15 @@
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# include <boost/python/detail/config.hpp>
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# include <boost/python/detail/wrap_python.hpp>
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# include <boost/type_traits/transform_traits.hpp>
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# include <boost/type_traits/cv_traits.hpp>
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# include <boost/type_traits/add_const.hpp>
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# include <boost/type_traits/add_reference.hpp>
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# include <boost/python/return_value_policy.hpp>
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# include <boost/python/return_by_value.hpp>
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# include <boost/python/return_internal_reference.hpp>
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# include <boost/python/object/function_object.hpp>
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# include <boost/python/arg_from_python.hpp>
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# include <boost/python/converter/builtin_converters.hpp>
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# include <boost/mpl/if.hpp>
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# include <boost/bind.hpp>
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namespace boost { namespace python {
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static PyObject* set(Data Class::*pm, PyObject* args_, PyObject*, Policies const& policies)
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{
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// check that each of the arguments is convertible
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arg_from_python<Class*> c0(PyTuple_GET_ITEM(args_, 0));
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arg_from_python<Class&> c0(PyTuple_GET_ITEM(args_, 0));
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if (!c0.convertible()) return 0;
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typedef typename add_const<Data>::type target1;
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if (!policies.precall(args_)) return 0;
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(c0(PyTuple_GET_ITEM(args_, 0)))->*pm = c1(PyTuple_GET_ITEM(args_, 1));
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(c0(PyTuple_GET_ITEM(args_, 0))).*pm = c1(PyTuple_GET_ITEM(args_, 1));
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return policies.postcall(args_, detail::none());
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}
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};
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// If it's a regular class type (not an object manager or other
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// type for which we have to_python specializations, use
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// return_internal_reference so that we can do things like
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// x.y.z = 1
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// and get the right result.
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template <class T>
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struct default_getter_policy
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: mpl::if_c<
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to_python_value<
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typename add_reference<
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typename add_const<T>::type
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>::type
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>::uses_registry
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, return_internal_reference<>
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, return_value_policy<return_by_value>
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>
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{};
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}
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template <class C, class D>
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object make_getter(D C::*pm)
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{
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typedef return_value_policy<return_by_value> default_policy;
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typedef typename detail::default_getter_policy<D>::type policy;
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return objects::function_object(
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::boost::bind(
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&detail::member<D,C,default_policy>::get, pm, _1, _2
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, default_policy())
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&detail::member<D,C,policy>::get, pm, _1, _2
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, policy())
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, 1);
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}

‎include/boost/python/to_python_value.hpp‎

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@@ -29,6 +29,11 @@ namespace detail
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static bool convertible();
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PyObject* operator()(argument_type) const;
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// This information helps make_getter() decide whether to try to
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// return an internal reference or not. I don't like it much,
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// but it will have to serve for now.
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BOOST_STATIC_CONSTANT(bool, uses_registry = false);
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};
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static bool convertible();
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PyObject* operator()(argument_type) const;
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// This information helps make_getter() decide whether to try to
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// return an internal reference or not. I don't like it much,
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// but it will have to serve for now.
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BOOST_STATIC_CONSTANT(bool, uses_registry = true);
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};
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}
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‎test/data_members.cpp‎

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@@ -24,12 +24,13 @@ double get_fair_value(X const& x) { return x.value(); }
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struct Var
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{
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Var(std::string name_) : name(name_), value(), name2(name.c_str()) {}
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Var(std::string name_) : name(name_), value(), name2(name.c_str()), y(6) {}
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std::string const name;
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std::string get_name1() const { return name; }
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std::string const& get_name2() const { return name; }
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float value;
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char const* name2;
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Y y;
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};
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BOOST_PYTHON_MODULE(data_members_ext)
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.def_readonly("name", &Var::name)
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.def_readonly("name2", &Var::name2)
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.def_readwrite("value", &Var::value)
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.def_readonly("y", &Var::y)
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// Test return_by_value for plain values and for
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// pointers... return_by_value was implemented as a

‎test/data_members.py‎

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>>> v.get_name2()
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'pi'
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>>> v.y.x
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6
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>>> v.y.x = -7
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>>> v.y.x
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-7
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'''
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def run(args = None):

‎todo.txt‎

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Wrap enums as a subclass of Python int
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High Priority:
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--------------
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Write "inside the Python type system", a survey of typeobject.c in
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Python source -- may go hand-in-hand with enum wrapping
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Document builtin correspondences between builtiin Python types and C++
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types
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Better overload resolution - choose best match
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Medium Priority:
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----------------
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Implement type_info streaming for GCC
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(http://mail.python.org/pipermail/c++-sig/2002-June/001277.html)
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Low Priority:
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------------
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Write "inside the Python type system", a survey of typeobject.c in
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Python source -- may go hand-in-hand with enum wrapping
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Better overload resolution - choose best match
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