6.1 Object Protocol
- int PyObject_Print(PyObject *o, FILE *fp, int flags)
-
Print an object o, on file fp. Returns
-1 on
error. The flags argument is used to enable certain printing
options. The only option currently supported is
Py_PRINT_RAW; if given, the str() of the
object is written instead of the repr().
- int PyObject_HasAttrString(PyObject *o, char *attr_name)
-
Returns
1 if o has the attribute attr_name, and
0 otherwise. This is equivalent to the Python expression
"hasattr(o, attr_name)". This function always
succeeds.
- PyObject* PyObject_GetAttrString(PyObject *o,
char *attr_name)
-
Return value:
New reference.
Retrieve an attribute named attr_name from object o.
Returns the attribute value on success, or NULL on failure.
This is the equivalent of the Python expression
"o.attr_name".
- int PyObject_HasAttr(PyObject *o, PyObject *attr_name)
-
Returns
1 if o has the attribute attr_name, and
0 otherwise. This is equivalent to the Python expression
"hasattr(o, attr_name)". This function always
succeeds.
- PyObject* PyObject_GetAttr(PyObject *o,
PyObject *attr_name)
-
Return value:
New reference.
Retrieve an attribute named attr_name from object o.
Returns the attribute value on success, or NULL on failure. This
is the equivalent of the Python expression
"o.attr_name".
- int PyObject_SetAttrString(PyObject *o,
char *attr_name, PyObject *v)
-
Set the value of the attribute named attr_name, for object
o, to the value v. Returns
-1 on failure. This
is the equivalent of the Python statement
"o.attr_name = v".
- int PyObject_SetAttr(PyObject *o,
PyObject *attr_name, PyObject *v)
-
Set the value of the attribute named attr_name, for object
o, to the value v. Returns
-1 on failure. This
is the equivalent of the Python statement
"o.attr_name = v".
- int PyObject_DelAttrString(PyObject *o, char *attr_name)
-
Delete attribute named attr_name, for object o. Returns
-1 on failure. This is the equivalent of the Python
statement: "del o.attr_name".
- int PyObject_DelAttr(PyObject *o, PyObject *attr_name)
-
Delete attribute named attr_name, for object o. Returns
-1 on failure. This is the equivalent of the Python
statement "del o.attr_name".
- PyObject* PyObject_RichCompare(PyObject *o1,
PyObject *o2, int opid)
-
Return value:
New reference.
Compare the values of o1 and o2 using the operation
specified by opid, which must be one of
Py_LT,
Py_LE,
Py_EQ,
Py_NE,
Py_GT, or
Py_GE, corresponding to
<,
<=,
==,
!=,
>, or
>= respectively. This is the equivalent of the Python expression
"o1 op o2", where op is the operator
corresponding to opid. Returns the value of the comparison on
success, or NULL on failure.
- int PyObject_RichCompareBool(PyObject *o1,
PyObject *o2, int opid)
-
Compare the values of o1 and o2 using the operation
specified by opid, which must be one of
Py_LT,
Py_LE,
Py_EQ,
Py_NE,
Py_GT, or
Py_GE, corresponding to
<,
<=,
==,
!=,
>, or
>= respectively. Returns -1 on error, 0 if the
result is false, 1 otherwise. This is the equivalent of the
Python expression "o1 op o2", where
op is the operator corresponding to opid.
- int PyObject_Cmp(PyObject *o1, PyObject *o2, int *result)
-
Compare the values of o1 and o2 using a routine provided
by o1, if one exists, otherwise with a routine provided by
o2. The result of the comparison is returned in
result. Returns
-1 on failure. This is the equivalent
of the Python statement "result =
cmp(o1, o2)".
- int PyObject_Compare(PyObject *o1, PyObject *o2)
-
Compare the values of o1 and o2 using a routine provided
by o1, if one exists, otherwise with a routine provided by
o2. Returns the result of the comparison on success. On
error, the value returned is undefined; use
PyErr_Occurred() to detect an error. This is equivalent
to the Python expression "cmp(o1,
o2)".
- PyObject* PyObject_Repr(PyObject *o)
-
Return value:
New reference.
Compute a string representation of object o. Returns the
string representation on success, NULL on failure. This is the
equivalent of the Python expression "repr(o)". Called by
the repr() built-in function and by
reverse quotes.
- PyObject* PyObject_Str(PyObject *o)
-
Return value:
New reference.
Compute a string representation of object o. Returns the
string representation on success, NULL on failure. This is the
equivalent of the Python expression "str(o)". Called by
the str() built-in function and by the
print statement.
- PyObject* PyObject_Unicode(PyObject *o)
-
Return value:
New reference.
Compute a Unicode string representation of object o. Returns
the Unicode string representation on success, NULL on failure.
This is the equivalent of the Python expression
"unicode(o)". Called by the
unicode() built-in function.
- int PyObject_IsInstance(PyObject *inst, PyObject *cls)
-
Return
1 if inst is an instance of the class cls
or a subclass of cls. If cls is a type object rather
than a class object, PyObject_IsInstance() returns
1 if inst is of type cls. If inst is not a
class instance and cls is neither a type object or class
object, inst must have a __class__ attribute -- the
class relationship of the value of that attribute with cls
will be used to determine the result of this function.
New in version 2.1.
Subclass determination is done in a fairly straightforward way, but
includes a wrinkle that implementors of extensions to the class system
may want to be aware of. If A and B are class
objects, B is a subclass of A if it inherits from
A either directly or indirectly. If either is not a class
object, a more general mechanism is used to determine the class
relationship of the two objects. When testing if B is a
subclass of A, if A is B,
PyObject_IsSubclass() returns true. If A and
B are different objects, B's __bases__ attribute
is searched in a depth-first fashion for A -- the presence of
the __bases__ attribute is considered sufficient for this
determination.
- int PyObject_IsSubclass(PyObject *derived,
PyObject *cls)
-
Returns
1 if the class derived is identical to or
derived from the class cls, otherwise returns 0. In
case of an error, returns -1. If either derived or
cls is not an actual class object, this function uses the
generic algorithm described above.
New in version 2.1.
- int PyCallable_Check(PyObject *o)
-
Determine if the object o is callable. Return
1 if the
object is callable and 0 otherwise. This function always
succeeds.
- PyObject* PyObject_CallObject(PyObject *callable_object,
PyObject *args)
-
Return value:
New reference.
Call a callable Python object callable_object, with arguments
given by the tuple args. If no arguments are needed, then
args may be NULL. Returns the result of the call on
success, or NULL on failure. This is the equivalent of the
Python expression "apply(callable_object, args)" or
"callable_object(*args)".
- PyObject* PyObject_CallFunction(PyObject *callable,
char *format, ...)
-
Return value:
New reference.
Call a callable Python object callable, with a variable
number of C arguments. The C arguments are described using a
Py_BuildValue() style format string. The format may be
NULL, indicating that no arguments are provided. Returns the
result of the call on success, or NULL on failure. This is the
equivalent of the Python expression "apply(callable,
args)" or "callable(*args)".
- PyObject* PyObject_CallMethod(PyObject *o,
char *method, char *format,
...)
-
Return value:
New reference.
Call the method named m of object o with a variable
number of C arguments. The C arguments are described by a
Py_BuildValue() format string. The format may be NULL,
indicating that no arguments are provided. Returns the result of the
call on success, or NULL on failure. This is the equivalent of
the Python expression "o.method(args)".
- PyObject* PyObject_CallFunctionObjArgs(PyObject *callable,
...,
NULL)
-
Return value:
New reference.
Call a callable Python object callable, with a variable
number of PyObject* arguments. The arguments are provided
as a variable number of parameters followed by NULL.
Returns the result of the call on success, or NULL on failure.
New in version 2.2.
- PyObject* PyObject_CallMethodObjArgs(PyObject *o,
PyObject *name,
...,
NULL)
-
Return value:
New reference.
Calls a method of the object o, where the name of the method
is given as a Python string object in name. It is called with
a variable number of PyObject* arguments. The arguments are
provided as a variable number of parameters followed by NULL.
Returns the result of the call on success, or NULL on failure.
New in version 2.2.
- int PyObject_Hash(PyObject *o)
-
Compute and return the hash value of an object o. On failure,
return
-1. This is the equivalent of the Python expression
"hash(o)".
- int PyObject_IsTrue(PyObject *o)
-
Returns
1 if the object o is considered to be true, and
0 otherwise. This is equivalent to the Python expression
"not not o". This function always succeeds.
- PyObject* PyObject_Type(PyObject *o)
-
Return value:
New reference.
When o is non-NULL, returns a type object corresponding to
the object type of object o. On failure, raises
SystemError and returns NULL. This is equivalent to
the Python expression type(o).
- int PyObject_TypeCheck(PyObject *o, PyTypeObject *type)
-
Return true if the object o is of type type or a subtype
of type. Both parameters must be non-NULL.
New in version 2.2.
- int PyObject_Length(PyObject *o)
-
Return the length of object o. If the object o provides
both sequence and mapping protocols, the sequence length is
returned. On error,
-1 is returned. This is the equivalent
to the Python expression "len(o)".
- PyObject* PyObject_GetItem(PyObject *o, PyObject *key)
-
Return value:
New reference.
Return element of o corresponding to the object key or
NULL on failure. This is the equivalent of the Python expression
"o[key]".
- int PyObject_SetItem(PyObject *o,
PyObject *key, PyObject *v)
-
Map the object key to the value v. Returns
-1 on
failure. This is the equivalent of the Python statement
"o[key] = v".
- int PyObject_DelItem(PyObject *o, PyObject *key)
-
Delete the mapping for key from o. Returns
-1 on
failure. This is the equivalent of the Python statement "del
o[key]".
- int PyObject_AsFileDescriptor(PyObject *o)
-
Derives a file-descriptor from a Python object. If the object is an
integer or long integer, its value is returned. If not, the
object's fileno() method is called if it exists; the method
must return an integer or long integer, which is returned as the
file descriptor value. Returns
-1 on failure.
- PyObject* PyObject_Dir(PyObject *o)
-
Return value:
New reference.
This is equivalent to the Python expression "dir(o)",
returning a (possibly empty) list of strings appropriate for the
object argument, or NULL if there was an error. If the argument
is NULL, this is like the Python "dir()", returning the names
of the current locals; in this case, if no execution frame is active
then NULL is returned but PyErr_Occurred() will
return false.
- PyObject* PyObject_GetIter(PyObject *o)
-
Return value:
New reference.
This is equivalent to the Python expression "iter(o)".
It returns a new iterator for the object argument, or the object
itself if the object is already an iterator. Raises
TypeError and returns NULL if the object cannot be
iterated.
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