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2.2.6 More Suggestions
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Remember that you can omit most of these functions, in which case you
provide
<code>0</code> as a value. There are type definitions for each of
the functions you must provide. They are in
<span class=
"file">object.h
</span> in the
Python include directory that comes with the source distribution of
In order to learn how to implement any specific method for your new
data type, do the following: Download and unpack the Python source
distribution. Go the
<span class=
"file">Objects
</span> directory, then search the
C source files for
<code>tp_
</code> plus the function you want (for
example,
<code>tp_print
</code> or
<code>tp_compare
</code>). You will find
examples of the function you want to implement.
When you need to verify that an object is an instance of the type
you are implementing, use the
<tt class=
"cfunction">PyObject_TypeCheck
</tt> function.
A sample of its use might be something like the following:
<div class=
"verbatim"><pre>
if (! PyObject_TypeCheck(some_object,
&MyType)) {
PyErr_SetString(PyExc_TypeError,
"arg #1 not a mything");
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<span class=
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2.4.2, documentation updated on
28 September
2005.
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