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diff --git a/libs/python/doc/html/faq/why_is_my_automatic_to_python_co.html b/libs/python/doc/html/faq/why_is_my_automatic_to_python_co.html new file mode 100644 index 0000000000..28d705aec8 --- /dev/null +++ b/libs/python/doc/html/faq/why_is_my_automatic_to_python_co.html @@ -0,0 +1,67 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> +<title>Why is my automatic to-python conversion not being found?</title> +<link rel="stylesheet" href="../boostbook.css" type="text/css"> +<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> +<link rel="home" href="../index.html" title="Boost.Python"> +<link rel="up" href="../faq.html" title="Chapter 4. Frequently Asked Questions (FAQs)"> +<link rel="prev" href="how_can_i_automatically_convert_.html" title="How can I automatically convert my custom string type to and from a Python string?"> +<link rel="next" href="is_boost_python_thread_aware_com.html" title="Is Boost.Python thread-aware/compatible with multiple interpreters?"> +</head> +<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> +<table cellpadding="2" width="100%"><tr><td valign="top"><img alt="" width="" height="" src="../images/boost.png"></td></tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="how_can_i_automatically_convert_.html"><img src="../images/prev.png" alt="Prev"></a><a accesskey="u" href="../faq.html"><img src="../images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../images/home.png" alt="Home"></a><a accesskey="n" href="is_boost_python_thread_aware_com.html"><img src="../images/next.png" alt="Next"></a> +</div> +<div class="section"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="faq.why_is_my_automatic_to_python_co"></a><a class="link" href="why_is_my_automatic_to_python_co.html" title="Why is my automatic to-python conversion not being found?">Why is my automatic + to-python conversion not being found?</a> +</h3></div></div></div> +<p> + <span class="emphasis"><em>Niall Douglas provides these notes:</em></span> + </p> +<p> + If you define custom converters similar to the ones shown above the <code class="computeroutput"><span class="identifier">def_readonly</span><span class="special">()</span></code> + and <code class="computeroutput"><span class="identifier">def_readwrite</span><span class="special">()</span></code> + member functions provided by <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">python</span><span class="special">::</span><span class="identifier">class_</span></code> + for direct access to your member data will not work as expected. This is + because <code class="computeroutput"><span class="identifier">def_readonly</span><span class="special">(</span><span class="string">"bar"</span><span class="special">,&</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">)</span></code> is equivalent to: + </p> +<pre class="programlisting"><span class="special">.</span><span class="identifier">add_property</span><span class="special">(</span><span class="string">"bar"</span><span class="special">,</span> <span class="identifier">make_getter</span><span class="special">(&</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">,</span> <span class="identifier">return_internal_reference</span><span class="special">()))</span> +</pre> +<p> + Similarly, <code class="computeroutput"><span class="identifier">def_readwrite</span><span class="special">(</span><span class="string">"bar"</span><span class="special">,&</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">)</span></code> + is equivalent to: + </p> +<pre class="programlisting"><span class="special">.</span><span class="identifier">add_property</span><span class="special">(</span><span class="string">"bar"</span><span class="special">,</span> <span class="identifier">make_getter</span><span class="special">(&</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">,</span> <span class="identifier">return_internal_reference</span><span class="special">()),</span> + <span class="identifier">make_setter</span><span class="special">(&</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">,</span> <span class="identifier">return_internal_reference</span><span class="special">())</span> +</pre> +<p> + In order to define return value policies compatible with the custom conversions + replace <code class="computeroutput"><span class="identifier">def_readonly</span><span class="special">()</span></code> + and <code class="computeroutput"><span class="identifier">def_readwrite</span><span class="special">()</span></code> + by <code class="computeroutput"><span class="identifier">add_property</span><span class="special">()</span></code>. + E.g.: + </p> +<pre class="programlisting"><span class="special">.</span><span class="identifier">add_property</span><span class="special">(</span><span class="string">"bar"</span><span class="special">,</span> <span class="identifier">make_getter</span><span class="special">(&</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">,</span> <span class="identifier">return_value_policy</span><span class="special"><</span><span class="identifier">return_by_value</span><span class="special">>()),</span> + <span class="identifier">make_setter</span><span class="special">(&</span><span class="identifier">foo</span><span class="special">::</span><span class="identifier">bar</span><span class="special">,</span> <span class="identifier">return_value_policy</span><span class="special"><</span><span class="identifier">return_by_value</span><span class="special">>()))</span> +</pre> +</div> +<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> +<td align="left"></td> +<td align="right"><div class="copyright-footer">Copyright © 2002-2015 David + Abrahams, Stefan Seefeld<p> + Distributed under the Boost Software License, Version 1.0. (See accompanying + file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) + </p> +</div></td> +</tr></table> +<hr> +<div class="spirit-nav"> +<a accesskey="p" href="how_can_i_automatically_convert_.html"><img src="../images/prev.png" alt="Prev"></a><a accesskey="u" href="../faq.html"><img src="../images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../images/home.png" alt="Home"></a><a accesskey="n" href="is_boost_python_thread_aware_com.html"><img src="../images/next.png" alt="Next"></a> +</div> +</body> +</html> |