1 .. highlightlang:: c 2 3 .. _sequence: 4 5 Sequence Protocol 6 ================= 7 8 9 .. c:function:: int PySequence_Check(PyObject *o) 10 11 Return ``1`` if the object provides sequence protocol, and ``0`` otherwise. 12 This function always succeeds. 13 14 15 .. c:function:: Py_ssize_t PySequence_Size(PyObject *o) 16 Py_ssize_t PySequence_Length(PyObject *o) 17 18 .. index:: builtin: len 19 20 Returns the number of objects in sequence *o* on success, and ``-1`` on 21 failure. This is equivalent to the Python expression ``len(o)``. 22 23 .. versionchanged:: 2.5 24 These functions returned an :c:type:`int` type. This might require 25 changes in your code for properly supporting 64-bit systems. 26 27 28 .. c:function:: PyObject* PySequence_Concat(PyObject *o1, PyObject *o2) 29 30 Return the concatenation of *o1* and *o2* on success, and *NULL* on failure. 31 This is the equivalent of the Python expression ``o1 + o2``. 32 33 34 .. c:function:: PyObject* PySequence_Repeat(PyObject *o, Py_ssize_t count) 35 36 Return the result of repeating sequence object *o* *count* times, or *NULL* on 37 failure. This is the equivalent of the Python expression ``o * count``. 38 39 .. versionchanged:: 2.5 40 This function used an :c:type:`int` type for *count*. This might require 41 changes in your code for properly supporting 64-bit systems. 42 43 44 .. c:function:: PyObject* PySequence_InPlaceConcat(PyObject *o1, PyObject *o2) 45 46 Return the concatenation of *o1* and *o2* on success, and *NULL* on failure. 47 The operation is done *in-place* when *o1* supports it. This is the equivalent 48 of the Python expression ``o1 += o2``. 49 50 51 .. c:function:: PyObject* PySequence_InPlaceRepeat(PyObject *o, Py_ssize_t count) 52 53 Return the result of repeating sequence object *o* *count* times, or *NULL* on 54 failure. The operation is done *in-place* when *o* supports it. This is the 55 equivalent of the Python expression ``o *= count``. 56 57 .. versionchanged:: 2.5 58 This function used an :c:type:`int` type for *count*. This might require 59 changes in your code for properly supporting 64-bit systems. 60 61 62 .. c:function:: PyObject* PySequence_GetItem(PyObject *o, Py_ssize_t i) 63 64 Return the *i*\ th element of *o*, or *NULL* on failure. This is the equivalent of 65 the Python expression ``o[i]``. 66 67 .. versionchanged:: 2.5 68 This function used an :c:type:`int` type for *i*. This might require 69 changes in your code for properly supporting 64-bit systems. 70 71 72 .. c:function:: PyObject* PySequence_GetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2) 73 74 Return the slice of sequence object *o* between *i1* and *i2*, or *NULL* on 75 failure. This is the equivalent of the Python expression ``o[i1:i2]``. 76 77 .. versionchanged:: 2.5 78 This function used an :c:type:`int` type for *i1* and *i2*. This might 79 require changes in your code for properly supporting 64-bit systems. 80 81 82 .. c:function:: int PySequence_SetItem(PyObject *o, Py_ssize_t i, PyObject *v) 83 84 Assign object *v* to the *i*\ th element of *o*. Raise an exception 85 and return ``-1`` on failure; return ``0`` on success. This 86 is the equivalent of the Python statement ``o[i] = v``. This function *does 87 not* steal a reference to *v*. 88 89 If *v* is *NULL*, the element is deleted, however this feature is 90 deprecated in favour of using :c:func:`PySequence_DelItem`. 91 92 .. versionchanged:: 2.5 93 This function used an :c:type:`int` type for *i*. This might require 94 changes in your code for properly supporting 64-bit systems. 95 96 97 .. c:function:: int PySequence_DelItem(PyObject *o, Py_ssize_t i) 98 99 Delete the *i*\ th element of object *o*. Returns ``-1`` on failure. This is the 100 equivalent of the Python statement ``del o[i]``. 101 102 .. versionchanged:: 2.5 103 This function used an :c:type:`int` type for *i*. This might require 104 changes in your code for properly supporting 64-bit systems. 105 106 107 .. c:function:: int PySequence_SetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2, PyObject *v) 108 109 Assign the sequence object *v* to the slice in sequence object *o* from *i1* to 110 *i2*. Raise an exception and return ``-1`` on failure; return ``0`` on success. 111 This is the equivalent of the Python statement ``o[i1:i2] = v``. 112 113 If *v* is *NULL*, the slice is deleted, however this feature is 114 deprecated in favour of using :c:func:`PySequence_DelSlice`. 115 116 .. versionchanged:: 2.5 117 This function used an :c:type:`int` type for *i1* and *i2*. This might 118 require changes in your code for properly supporting 64-bit systems. 119 120 121 .. c:function:: int PySequence_DelSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2) 122 123 Delete the slice in sequence object *o* from *i1* to *i2*. Returns ``-1`` on 124 failure. This is the equivalent of the Python statement ``del o[i1:i2]``. 125 126 .. versionchanged:: 2.5 127 This function used an :c:type:`int` type for *i1* and *i2*. This might 128 require changes in your code for properly supporting 64-bit systems. 129 130 131 .. c:function:: Py_ssize_t PySequence_Count(PyObject *o, PyObject *value) 132 133 Return the number of occurrences of *value* in *o*, that is, return the number 134 of keys for which ``o[key] == value``. On failure, return ``-1``. This is 135 equivalent to the Python expression ``o.count(value)``. 136 137 .. versionchanged:: 2.5 138 This function returned an :c:type:`int` type. This might require changes 139 in your code for properly supporting 64-bit systems. 140 141 142 .. c:function:: int PySequence_Contains(PyObject *o, PyObject *value) 143 144 Determine if *o* contains *value*. If an item in *o* is equal to *value*, 145 return ``1``, otherwise return ``0``. On error, return ``-1``. This is 146 equivalent to the Python expression ``value in o``. 147 148 149 .. c:function:: Py_ssize_t PySequence_Index(PyObject *o, PyObject *value) 150 151 Return the first index *i* for which ``o[i] == value``. On error, return 152 ``-1``. This is equivalent to the Python expression ``o.index(value)``. 153 154 .. versionchanged:: 2.5 155 This function returned an :c:type:`int` type. This might require changes 156 in your code for properly supporting 64-bit systems. 157 158 159 .. c:function:: PyObject* PySequence_List(PyObject *o) 160 161 Return a list object with the same contents as the arbitrary sequence *o*. The 162 returned list is guaranteed to be new. 163 164 165 .. c:function:: PyObject* PySequence_Tuple(PyObject *o) 166 167 .. index:: builtin: tuple 168 169 Return a tuple object with the same contents as the arbitrary sequence *o* or 170 *NULL* on failure. If *o* is a tuple, a new reference will be returned, 171 otherwise a tuple will be constructed with the appropriate contents. This is 172 equivalent to the Python expression ``tuple(o)``. 173 174 175 .. c:function:: PyObject* PySequence_Fast(PyObject *o, const char *m) 176 177 Return the sequence *o* as a list, unless it is already a tuple or list, in 178 which case *o* is returned. Use :c:func:`PySequence_Fast_GET_ITEM` to access 179 the members of the result. Returns *NULL* on failure. If the object is not 180 a sequence, raises :exc:`TypeError` with *m* as the message text. 181 182 183 .. c:function:: PyObject* PySequence_Fast_GET_ITEM(PyObject *o, Py_ssize_t i) 184 185 Return the *i*\ th element of *o*, assuming that *o* was returned by 186 :c:func:`PySequence_Fast`, *o* is not *NULL*, and that *i* is within bounds. 187 188 .. versionchanged:: 2.5 189 This function used an :c:type:`int` type for *i*. This might require 190 changes in your code for properly supporting 64-bit systems. 191 192 193 .. c:function:: PyObject** PySequence_Fast_ITEMS(PyObject *o) 194 195 Return the underlying array of PyObject pointers. Assumes that *o* was returned 196 by :c:func:`PySequence_Fast` and *o* is not *NULL*. 197 198 Note, if a list gets resized, the reallocation may relocate the items array. 199 So, only use the underlying array pointer in contexts where the sequence 200 cannot change. 201 202 .. versionadded:: 2.4 203 204 205 .. c:function:: PyObject* PySequence_ITEM(PyObject *o, Py_ssize_t i) 206 207 Return the *i*\ th element of *o* or *NULL* on failure. Macro form of 208 :c:func:`PySequence_GetItem` but without checking that 209 :c:func:`PySequence_Check` on *o* is true and without adjustment for negative 210 indices. 211 212 .. versionadded:: 2.3 213 214 .. versionchanged:: 2.5 215 This function used an :c:type:`int` type for *i*. This might require 216 changes in your code for properly supporting 64-bit systems. 217 218 219 .. c:function:: Py_ssize_t PySequence_Fast_GET_SIZE(PyObject *o) 220 221 Returns the length of *o*, assuming that *o* was returned by 222 :c:func:`PySequence_Fast` and that *o* is not *NULL*. The size can also be 223 gotten by calling :c:func:`PySequence_Size` on *o*, but 224 :c:func:`PySequence_Fast_GET_SIZE` is faster because it can assume *o* is a list 225 or tuple. 226
