add stl_input_iterator for wrapping a Python iterator in a STL input iterator

[SVN r31513]

include/boost/python/object/stl_iterator_core.hpp

@@ -0,0 +1,27 @@
+// Copyright Eric Niebler 2005.
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+#ifndef STL_ITERATOR_CORE_EAN20051028_HPP
+# define STL_ITERATOR_CORE_EAN20051028_HPP
+
+# include <boost/python/object_fwd.hpp>
+# include <boost/python/handle_fwd.hpp>
+
+namespace boost { namespace python { namespace objects {
+
+struct BOOST_PYTHON_DECL stl_input_iterator_impl
+{
+    stl_input_iterator_impl();
+    stl_input_iterator_impl(boost::python::object const &ob);
+    void increment();
+    bool equal(stl_input_iterator_impl const &that) const;
+    boost::python::handle<> const &current() const;
+private:
+    boost::python::object it_;
+    boost::python::handle<> ob_;
+};
+
+}}} // namespace boost::python::object
+
+#endif // STL_ITERATOR_CORE_EAN20051028_HPP

include/boost/python/stl_iterator.hpp

@@ -0,0 +1,61 @@
+// Copyright Eric Niebler 2005.
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+#ifndef STL_ITERATOR_EAN20051028_HPP
+# define STL_ITERATOR_EAN20051028_HPP
+
+# include <boost/python/detail/prefix.hpp>
+
+# include <boost/python/object/stl_iterator_core.hpp>
+
+# include <boost/iterator/iterator_facade.hpp>
+
+namespace boost { namespace python
+{ 
+
+// An STL input iterator over a python sequence
+template<typename ValueT>
+struct stl_input_iterator
+  : boost::iterator_facade<
+        stl_input_iterator<ValueT>
+      , ValueT
+      , std::input_iterator_tag
+      , ValueT
+    >
+{
+    stl_input_iterator()
+      : impl_()
+    {
+    }
+
+    // ob is the python sequence
+    stl_input_iterator(boost::python::object const &ob)
+      : impl_(ob)
+    {
+    }
+
+private:
+    friend class iterator_core_access;
+
+    void increment()
+    {
+        this->impl_.increment();
+    }
+
+    ValueT dereference() const
+    {
+        return extract<ValueT>(this->impl_.current().get())();
+    }
+
+    bool equal(stl_input_iterator<ValueT> const &that) const
+    {
+        return this->impl_.equal(that.impl_);
+    }
+
+    objects::stl_input_iterator_impl impl_;
+};
+
+}} // namespace boost::python
+
+#endif // STL_ITERATOR_EAN20051028_HPP