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".

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.

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(o, args)".

PyObject* PyObject_CallFunction (PyObject *callable_object, char *format, ...): Return value: New reference.
Call a callable Python object callable_object, 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(o, args)".

PyObject* PyObject_CallMethod (PyObject *o, char *m, 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)". Note that special method names, such as __add__(), __getitem__(), and so on are not supported. The specific abstract-object routines for these must be used.

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.
On success, returns a type object corresponding to the object type of object o. On failure, returns NULL. This is equivalent to the Python expression "type(o)".

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.

See About this document... for information on suggesting changes.