1 .. highlightlang:: c 2 3 .. _tupleobjects: 4 5 Tuple Objects 6 ------------- 7 8 .. index:: object: tuple 9 10 11 .. c:type:: PyTupleObject 12 13 This subtype of :c:type:`PyObject` represents a Python tuple object. 14 15 16 .. c:var:: PyTypeObject PyTuple_Type 17 18 .. index:: single: TupleType (in module types) 19 20 This instance of :c:type:`PyTypeObject` represents the Python tuple type; it is 21 the same object as ``tuple`` and ``types.TupleType`` in the Python layer.. 22 23 24 .. c:function:: int PyTuple_Check(PyObject *p) 25 26 Return true if *p* is a tuple object or an instance of a subtype of the tuple 27 type. 28 29 .. versionchanged:: 2.2 30 Allowed subtypes to be accepted. 31 32 33 .. c:function:: int PyTuple_CheckExact(PyObject *p) 34 35 Return true if *p* is a tuple object, but not an instance of a subtype of the 36 tuple type. 37 38 .. versionadded:: 2.2 39 40 41 .. c:function:: PyObject* PyTuple_New(Py_ssize_t len) 42 43 Return a new tuple object of size *len*, or *NULL* on failure. 44 45 .. versionchanged:: 2.5 46 This function used an :c:type:`int` type for *len*. This might require 47 changes in your code for properly supporting 64-bit systems. 48 49 50 .. c:function:: PyObject* PyTuple_Pack(Py_ssize_t n, ...) 51 52 Return a new tuple object of size *n*, or *NULL* on failure. The tuple values 53 are initialized to the subsequent *n* C arguments pointing to Python objects. 54 ``PyTuple_Pack(2, a, b)`` is equivalent to ``Py_BuildValue("(OO)", a, b)``. 55 56 .. versionadded:: 2.4 57 58 .. versionchanged:: 2.5 59 This function used an :c:type:`int` type for *n*. This might require 60 changes in your code for properly supporting 64-bit systems. 61 62 63 .. c:function:: Py_ssize_t PyTuple_Size(PyObject *p) 64 65 Take a pointer to a tuple object, and return the size of that tuple. 66 67 .. versionchanged:: 2.5 68 This function returned an :c:type:`int` type. This might require changes 69 in your code for properly supporting 64-bit systems. 70 71 72 .. c:function:: Py_ssize_t PyTuple_GET_SIZE(PyObject *p) 73 74 Return the size of the tuple *p*, which must be non-*NULL* and point to a tuple; 75 no error checking is performed. 76 77 .. versionchanged:: 2.5 78 This function returned an :c:type:`int` type. This might require changes 79 in your code for properly supporting 64-bit systems. 80 81 82 .. c:function:: PyObject* PyTuple_GetItem(PyObject *p, Py_ssize_t pos) 83 84 Return the object at position *pos* in the tuple pointed to by *p*. If *pos* is 85 out of bounds, return *NULL* and sets an :exc:`IndexError` exception. 86 87 .. versionchanged:: 2.5 88 This function used an :c:type:`int` type for *pos*. This might require 89 changes in your code for properly supporting 64-bit systems. 90 91 92 .. c:function:: PyObject* PyTuple_GET_ITEM(PyObject *p, Py_ssize_t pos) 93 94 Like :c:func:`PyTuple_GetItem`, but does no checking of its arguments. 95 96 .. versionchanged:: 2.5 97 This function used an :c:type:`int` type for *pos*. This might require 98 changes in your code for properly supporting 64-bit systems. 99 100 101 .. c:function:: PyObject* PyTuple_GetSlice(PyObject *p, Py_ssize_t low, Py_ssize_t high) 102 103 Take a slice of the tuple pointed to by *p* from *low* to *high* and return it 104 as a new tuple. 105 106 .. versionchanged:: 2.5 107 This function used an :c:type:`int` type for *low* and *high*. This might 108 require changes in your code for properly supporting 64-bit systems. 109 110 111 .. c:function:: int PyTuple_SetItem(PyObject *p, Py_ssize_t pos, PyObject *o) 112 113 Insert a reference to object *o* at position *pos* of the tuple pointed to by 114 *p*. Return ``0`` on success. 115 116 .. note:: 117 118 This function "steals" a reference to *o*. 119 120 .. versionchanged:: 2.5 121 This function used an :c:type:`int` type for *pos*. This might require 122 changes in your code for properly supporting 64-bit systems. 123 124 125 .. c:function:: void PyTuple_SET_ITEM(PyObject *p, Py_ssize_t pos, PyObject *o) 126 127 Like :c:func:`PyTuple_SetItem`, but does no error checking, and should *only* be 128 used to fill in brand new tuples. 129 130 .. note:: 131 132 This function "steals" a reference to *o*. 133 134 .. versionchanged:: 2.5 135 This function used an :c:type:`int` type for *pos*. This might require 136 changes in your code for properly supporting 64-bit systems. 137 138 139 .. c:function:: int _PyTuple_Resize(PyObject **p, Py_ssize_t newsize) 140 141 Can be used to resize a tuple. *newsize* will be the new length of the tuple. 142 Because tuples are *supposed* to be immutable, this should only be used if there 143 is only one reference to the object. Do *not* use this if the tuple may already 144 be known to some other part of the code. The tuple will always grow or shrink 145 at the end. Think of this as destroying the old tuple and creating a new one, 146 only more efficiently. Returns ``0`` on success. Client code should never 147 assume that the resulting value of ``*p`` will be the same as before calling 148 this function. If the object referenced by ``*p`` is replaced, the original 149 ``*p`` is destroyed. On failure, returns ``-1`` and sets ``*p`` to *NULL*, and 150 raises :exc:`MemoryError` or :exc:`SystemError`. 151 152 .. versionchanged:: 2.2 153 Removed unused third parameter, *last_is_sticky*. 154 155 .. versionchanged:: 2.5 156 This function used an :c:type:`int` type for *newsize*. This might 157 require changes in your code for properly supporting 64-bit systems. 158 159 160 .. c:function:: int PyTuple_ClearFreeList() 161 162 Clear the free list. Return the total number of freed items. 163 164 .. versionadded:: 2.6 165
