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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I noticed the following changes in the C API manuals from 3.3.5 (and earlier versions) to 3.4. I don’t know if these changes are deliberate and imply that we C extension developers no longer need to care about ‘reference ownership’ because
of some improvements in 3.4. Could anyone clarify it? <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Jianfeng<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:16.0pt">--- 3.4 C API reference manual ----<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3/c-api/structures.html#c.PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a>*<span class="apple-converted-space"> </span></span><tt><b><span style="font-size:14.5pt;color:#222222">PySequence_GetItem</span></b></tt><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">(</span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3/c-api/structures.html#c.PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a><em><span style="font-family:"Arial","sans-serif""> *o</span></em>,
Py_ssize_t<em><span style="font-family:"Arial","sans-serif""> i</span></em></span><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">)</span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3/c-api/sequence.html#c.PySequence_GetItem" title="Permalink to this definition"><span style="font-size:9.5pt;color:#30306F;text-decoration:none">¶</span></a><o:p></o:p></span></p>
<p style="mso-margin-top-alt:0in;margin-right:0in;margin-bottom:5.0pt;margin-left:.5in;text-align:justify;text-justify:inter-ideograph;line-height:16.8pt;background:white">
<span style="font-family:"Arial","sans-serif";color:#222222">Return the</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">i</span></em><span style="font-family:"Arial","sans-serif";color:#222222">th
element of</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">o</span></em><span style="font-family:"Arial","sans-serif";color:#222222">,
or</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">NULL</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">on
failure. This is the equivalent of the Python expression</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span class="pre"><span style="font-size:11.5pt;font-family:"Courier New";color:#222222;background:#ECF0F3">o[i]</span></span><span style="font-family:"Arial","sans-serif";color:#222222">.<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.4/c-api/structures.html#c.PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a>*<span class="apple-converted-space"> </span></span><tt><b><span style="font-size:14.5pt;color:#222222">PyList_GetItem</span></b></tt><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">(</span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.4/c-api/structures.html#c.PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a><em><span style="font-family:"Arial","sans-serif""> *list</span></em>,
Py_ssize_t<em><span style="font-family:"Arial","sans-serif""> index</span></em></span><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">)</span><span style="font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p style="mso-margin-top-alt:0in;margin-right:0in;margin-bottom:5.0pt;margin-left:.5in;text-align:justify;text-justify:inter-ideograph;line-height:16.8pt;background:white">
<span style="font-family:"Arial","sans-serif";color:#222222">Return the object at position</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">index</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">in
the list pointed to by</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">list</span></em><span style="font-family:"Arial","sans-serif";color:#222222">.
The position must be positive, indexing from the end of the list is not supported. If</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">index</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">is
out of bounds, return</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">NULL</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">and
set an</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.4/library/exceptions.html#IndexError" title="IndexError"><span class="pre"><span style="font-size:11.5pt;font-family:"Courier New";color:#30306F;text-decoration:none">IndexError</span></span></a></span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">exception.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black;mso-fareast-language:ZH-CN"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:16.0pt;color:black;mso-fareast-language:ZH-CN">--- 3.3.5 C API reference manual ---<o:p></o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.3/c-api/structures.html#PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a>*<span class="apple-converted-space"> </span></span><tt><b><span style="font-size:14.5pt;color:#222222">PySequence_GetItem</span></b></tt><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">(</span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.3/c-api/structures.html#PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a><em><span style="font-family:"Arial","sans-serif""> *o</span></em>,
Py_ssize_t<em><span style="font-family:"Arial","sans-serif""> i</span></em></span><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">)</span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.3/c-api/sequence.html#PySequence_GetItem" title="Permalink to this definition"><span style="font-size:9.5pt;color:#30306F;text-decoration:none">¶</span></a><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:2.25pt;margin-right:0in;margin-bottom:7.5pt;margin-left:.5in;text-align:justify;text-justify:inter-ideograph;line-height:15.6pt;background:white">
<em><span style="font-family:"Arial","sans-serif";color:#006600">Return value: New reference.</span></em><span style="font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p style="mso-margin-top-alt:0in;margin-right:0in;margin-bottom:5.0pt;margin-left:.5in;text-align:justify;text-justify:inter-ideograph;line-height:16.8pt;background:white">
<span style="font-family:"Arial","sans-serif";color:#222222">Return the</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">i</span></em><span style="font-family:"Arial","sans-serif";color:#222222">th
element of</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">o</span></em><span style="font-family:"Arial","sans-serif";color:#222222">,
or</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">NULL</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">on
failure. This is the equivalent of the Python expression</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span class="pre"><span style="font-size:11.5pt;font-family:"Courier New";color:#222222;background:#ECF0F3">o[i]</span></span><span style="font-family:"Arial","sans-serif";color:#222222">.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black;mso-fareast-language:ZH-CN"><o:p> </o:p></span></p>
<p class="MsoNormal" style="background:white"><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.3/c-api/structures.html#PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a>*<span class="apple-converted-space"> </span></span><tt><b><span style="font-size:14.5pt;color:#222222">PyList_GetItem</span></b></tt><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">(</span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.3/c-api/structures.html#PyObject" title="PyObject"><span style="color:#30306F;text-decoration:none">PyObject</span></a><em><span style="font-family:"Arial","sans-serif""> *list</span></em>,
Py_ssize_t<em><span style="font-family:"Arial","sans-serif""> index</span></em></span><span style="font-size:13.5pt;font-family:"Arial","sans-serif";color:#222222">)</span><span style="font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:2.25pt;margin-right:0in;margin-bottom:7.5pt;margin-left:.5in;text-align:justify;text-justify:inter-ideograph;line-height:15.6pt;background:white">
<em><span style="font-family:"Arial","sans-serif";color:#006600">Return value: Borrowed reference.</span></em><span style="font-family:"Arial","sans-serif";color:#222222"><o:p></o:p></span></p>
<p style="mso-margin-top-alt:0in;margin-right:0in;margin-bottom:5.0pt;margin-left:.5in;text-align:justify;text-justify:inter-ideograph;line-height:16.8pt;background:white">
<span style="font-family:"Arial","sans-serif";color:#222222">Return the object at position</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">index</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">in
the list pointed to by</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">list</span></em><span style="font-family:"Arial","sans-serif";color:#222222">.
The position must be positive, indexing from the end of the list is not supported. If</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">index</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">is
out of bounds, return</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><em><span style="font-family:"Arial","sans-serif";color:#222222">NULL</span></em><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">and
set an</span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222"><a href="https://docs.python.org/3.3/library/exceptions.html#IndexError" title="IndexError"><span class="pre"><span style="font-size:11.5pt;font-family:"Courier New";color:#30306F;text-decoration:none">IndexError</span></span></a></span><span class="apple-converted-space"><span style="font-family:"Arial","sans-serif";color:#222222"> </span></span><span style="font-family:"Arial","sans-serif";color:#222222">exception.<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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