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7.3.2.2 Methods and Slot Functions

The following APIs are capable of handling Unicode objects and strings on input (we refer to them as strings in the descriptions) and return Unicode objects or integers as apporpriate.

They all return `NULL` or `-1` if an exception occurs.

PyObject* `PyUnicode_Concat`(PyObject *left, PyObject *right)
  Return value: New reference.
  Concat two strings giving a new Unicode string.

PyObject* `PyUnicode_Split`(PyObject *s, PyObject *sep, int maxsplit)
  Return value: New reference.
  Split a string giving a list of Unicode strings. If sep is `NULL`, splitting will be done at all whitespace substrings. Otherwise, splits occur at the given separator. At most maxsplit splits will be done. If negative, no limit is set. Separators are not included in the resulting list.

PyObject* `PyUnicode_Splitlines`(PyObject *s, int maxsplit)
  Return value: New reference.
  Split a Unicode string at line breaks, returning a list of Unicode strings. CRLF is considered to be one line break. The Line break characters are not included in the resulting strings.

PyObject* `PyUnicode_Translate`(PyObject *str, PyObject *table, const char *errors)
  Return value: New reference.
  Translate a string by applying a character mapping table to it and return the resulting Unicode object.

  The mapping table must map Unicode ordinal integers to Unicode ordinal integers or None (causing deletion of the character).

  Mapping tables need only provide the `__getitem__()` interface; dictionaries and sequences work well. Unmapped character ordinals (ones which cause a `LookupError`) are left untouched and are copied as-is.

  errors has the usual meaning for codecs. It may be `NULL` which indicates to use the default error handling.

PyObject* `PyUnicode_Join`(PyObject *separator, PyObject *seq)
  Return value: New reference.
  Join a sequence of strings using the given separator and return the resulting Unicode string.

PyObject* `PyUnicode_Tailmatch`(PyObject *str, PyObject *substr, int start, int end, int direction)
  Return value: New reference.
  Return 1 if substr matches str[start:end] at the given tail end (direction == -1 means to do a prefix match, direction == 1 a suffix match), 0 otherwise.

PyObject* `PyUnicode_Find`(PyObject *str, PyObject *substr, int start, int end, int direction)
  Return value: New reference.
  Return the first position of substr in str[start:end] using the given direction (direction == 1 means to do a forward search, direction == -1 a backward search), 0 otherwise.

PyObject* `PyUnicode_Count`(PyObject *str, PyObject *substr, int start, int end)
  Return value: New reference.
  Count the number of occurrences of substr in str[start:end]

PyObject* `PyUnicode_Replace`(PyObject *str, PyObject *substr, PyObject *replstr, int maxcount)
  Return value: New reference.
  Replace at most maxcount occurrences of substr in str with replstr and return the resulting Unicode object. maxcount == -1 means replace all occurrences.

int `PyUnicode_Compare`(PyObject *left, PyObject *right)
  Compare two strings and return -1, 0, 1 for less than, equal, and greater than, respectively.

PyObject* `PyUnicode_Format`(PyObject *format, PyObject *args)
  Return value: New reference.
  Returns a new string object from format and args; this is analogous to `format % args`. The args argument must be a tuple.

int `PyUnicode_Contains`(PyObject *container, PyObject *element)
  Checks whether element is contained in container and returns true or false accordingly.

  element has to coerce to a one element Unicode string. `-1` is returned if there was an error.