From 95cd91c17f4c3ce5eab27551150f5e92ecb1bc22 Mon Sep 17 00:00:00 2001 From: Ezio Melotti Date: Thu, 14 Apr 2011 07:43:53 +0300 Subject: [PATCH] #11840: Improve c-api/unicode documentation. Patch by Sandro Tosi. --- Doc/c-api/unicode.rst | 56 +++++++++++++++++++++---------------------- 1 file changed, 27 insertions(+), 29 deletions(-) diff --git a/Doc/c-api/unicode.rst b/Doc/c-api/unicode.rst index de493de6e5f..a91f258e587 100644 --- a/Doc/c-api/unicode.rst +++ b/Doc/c-api/unicode.rst @@ -329,8 +329,8 @@ APIs: incremented refcount. :class:`bytes`, :class:`bytearray` and other char buffer compatible objects - are decoded according to the given encoding and using the error handling - defined by errors. Both can be *NULL* to have the interface use the default + are decoded according to the given *encoding* and using the error handling + defined by *errors*. Both can be *NULL* to have the interface use the default values (see the next section for details). All other objects, including Unicode objects, cause a :exc:`TypeError` to be @@ -390,12 +390,12 @@ used, passing :cfunc:`PyUnicode_FSConverter` as the conversion function: wchar_t Support """"""""""""""" -wchar_t support for platforms which support it: +:ctype:`wchar_t` support for platforms which support it: .. cfunction:: PyObject* PyUnicode_FromWideChar(const wchar_t *w, Py_ssize_t size) - Create a Unicode object from the :ctype:`wchar_t` buffer *w* of the given size. - Passing -1 as the size indicates that the function must itself compute the length, + Create a Unicode object from the :ctype:`wchar_t` buffer *w* of the given *size*. + Passing -1 as the *size* indicates that the function must itself compute the length, using wcslen. Return *NULL* on failure. @@ -419,15 +419,15 @@ Built-in Codecs Python provides a set of built-in codecs which are written in C for speed. All of these codecs are directly usable via the following functions. -Many of the following APIs take two arguments encoding and errors. These -parameters encoding and errors have the same semantics as the ones of the -built-in :func:`str` string object constructor. +Many of the following APIs take two arguments encoding and errors, and they +have the same semantics as the ones of the built-in :func:`str` string object +constructor. Setting encoding to *NULL* causes the default encoding to be used which is ASCII. The file system calls should use :cfunc:`PyUnicode_FSConverter` for encoding file names. This uses the variable :cdata:`Py_FileSystemDefaultEncoding` internally. This -variable should be treated as read-only: On some systems, it will be a +variable should be treated as read-only: on some systems, it will be a pointer to a static string, on others, it will change at run-time (such as when the application invokes setlocale). @@ -456,7 +456,7 @@ These are the generic codec APIs: .. cfunction:: PyObject* PyUnicode_Encode(const Py_UNICODE *s, Py_ssize_t size, const char *encoding, const char *errors) - Encode the :ctype:`Py_UNICODE` buffer of the given size and return a Python + Encode the :ctype:`Py_UNICODE` buffer *s* of the given *size* and return a Python bytes object. *encoding* and *errors* have the same meaning as the parameters of the same name in the Unicode :meth:`encode` method. The codec to be used is looked up using the Python codec registry. Return *NULL* if an @@ -494,7 +494,7 @@ These are the UTF-8 codec APIs: .. cfunction:: PyObject* PyUnicode_EncodeUTF8(const Py_UNICODE *s, Py_ssize_t size, const char *errors) - Encode the :ctype:`Py_UNICODE` buffer of the given size using UTF-8 and + Encode the :ctype:`Py_UNICODE` buffer *s* of the given *size* using UTF-8 and return a Python bytes object. Return *NULL* if an exception was raised by the codec. @@ -514,7 +514,7 @@ These are the UTF-32 codec APIs: .. cfunction:: PyObject* PyUnicode_DecodeUTF32(const char *s, Py_ssize_t size, const char *errors, int *byteorder) - Decode *length* bytes from a UTF-32 encoded buffer string and return the + Decode *size* bytes from a UTF-32 encoded buffer string and return the corresponding Unicode object. *errors* (if non-*NULL*) defines the error handling. It defaults to "strict". @@ -582,7 +582,7 @@ These are the UTF-16 codec APIs: .. cfunction:: PyObject* PyUnicode_DecodeUTF16(const char *s, Py_ssize_t size, const char *errors, int *byteorder) - Decode *length* bytes from a UTF-16 encoded buffer string and return the + Decode *size* bytes from a UTF-16 encoded buffer string and return the corresponding Unicode object. *errors* (if non-*NULL*) defines the error handling. It defaults to "strict". @@ -714,7 +714,7 @@ These are the "Raw Unicode Escape" codec APIs: .. cfunction:: PyObject* PyUnicode_EncodeRawUnicodeEscape(const Py_UNICODE *s, Py_ssize_t size, const char *errors) - Encode the :ctype:`Py_UNICODE` buffer of the given size using Raw-Unicode-Escape + Encode the :ctype:`Py_UNICODE` buffer of the given *size* using Raw-Unicode-Escape and return a Python string object. Return *NULL* if an exception was raised by the codec. @@ -741,7 +741,7 @@ ordinals and only these are accepted by the codecs during encoding. .. cfunction:: PyObject* PyUnicode_EncodeLatin1(const Py_UNICODE *s, Py_ssize_t size, const char *errors) - Encode the :ctype:`Py_UNICODE` buffer of the given size using Latin-1 and + Encode the :ctype:`Py_UNICODE` buffer of the given *size* using Latin-1 and return a Python bytes object. Return *NULL* if an exception was raised by the codec. @@ -768,7 +768,7 @@ codes generate errors. .. cfunction:: PyObject* PyUnicode_EncodeASCII(const Py_UNICODE *s, Py_ssize_t size, const char *errors) - Encode the :ctype:`Py_UNICODE` buffer of the given size using ASCII and + Encode the :ctype:`Py_UNICODE` buffer of the given *size* using ASCII and return a Python bytes object. Return *NULL* if an exception was raised by the codec. @@ -783,8 +783,6 @@ codes generate errors. Character Map Codecs """""""""""""""""""" -These are the mapping codec APIs: - This codec is special in that it can be used to implement many different codecs (and this is in fact what was done to obtain most of the standard codecs included in the :mod:`encodings` package). The codec uses mapping to encode and @@ -806,6 +804,7 @@ meaning that its ordinal value will be interpreted as Unicode or Latin-1 ordinal resp. Because of this, mappings only need to contain those mappings which map characters to different code points. +These are the mapping codec APIs: .. cfunction:: PyObject* PyUnicode_DecodeCharmap(const char *s, Py_ssize_t size, PyObject *mapping, const char *errors) @@ -819,7 +818,7 @@ characters to different code points. .. cfunction:: PyObject* PyUnicode_EncodeCharmap(const Py_UNICODE *s, Py_ssize_t size, PyObject *mapping, const char *errors) - Encode the :ctype:`Py_UNICODE` buffer of the given size using the given + Encode the :ctype:`Py_UNICODE` buffer of the given *size* using the given *mapping* object and return a Python string object. Return *NULL* if an exception was raised by the codec. @@ -835,7 +834,7 @@ The following codec API is special in that maps Unicode to Unicode. .. cfunction:: PyObject* PyUnicode_TranslateCharmap(const Py_UNICODE *s, Py_ssize_t size, PyObject *table, const char *errors) - Translate a :ctype:`Py_UNICODE` buffer of the given length by applying a + Translate a :ctype:`Py_UNICODE` buffer of the given *size* by applying a character mapping *table* to it and return the resulting Unicode object. Return *NULL* when an exception was raised by the codec. @@ -847,16 +846,15 @@ The following codec API is special in that maps Unicode to Unicode. :exc:`LookupError`) are left untouched and are copied as-is. +MBCS codecs for Windows +""""""""""""""""""""""" + These are the MBCS codec APIs. They are currently only available on Windows and use the Win32 MBCS converters to implement the conversions. Note that MBCS (or DBCS) is a class of encodings, not just one. The target encoding is defined by the user settings on the machine running the codec. -MBCS codecs for Windows -""""""""""""""""""""""" - - .. cfunction:: PyObject* PyUnicode_DecodeMBCS(const char *s, Py_ssize_t size, const char *errors) Create a Unicode object by decoding *size* bytes of the MBCS encoded string *s*. @@ -873,7 +871,7 @@ MBCS codecs for Windows .. cfunction:: PyObject* PyUnicode_EncodeMBCS(const Py_UNICODE *s, Py_ssize_t size, const char *errors) - Encode the :ctype:`Py_UNICODE` buffer of the given size using MBCS and return + Encode the :ctype:`Py_UNICODE` buffer of the given *size* using MBCS and return a Python bytes object. Return *NULL* if an exception was raised by the codec. @@ -908,7 +906,7 @@ They all return *NULL* or ``-1`` if an exception occurs. .. cfunction:: PyObject* PyUnicode_Split(PyObject *s, PyObject *sep, Py_ssize_t maxsplit) - Split a string giving a list of Unicode strings. If sep is *NULL*, splitting + 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. @@ -939,20 +937,20 @@ They all return *NULL* or ``-1`` if an exception occurs. .. cfunction:: PyObject* PyUnicode_Join(PyObject *separator, PyObject *seq) - Join a sequence of strings using the given separator and return the resulting + Join a sequence of strings using the given *separator* and return the resulting Unicode string. .. cfunction:: int PyUnicode_Tailmatch(PyObject *str, PyObject *substr, Py_ssize_t start, Py_ssize_t end, int direction) - Return 1 if *substr* matches *str*[*start*:*end*] at the given tail end + 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. Return ``-1`` if an error occurred. .. cfunction:: Py_ssize_t PyUnicode_Find(PyObject *str, PyObject *substr, Py_ssize_t start, Py_ssize_t end, int direction) - Return the first position of *substr* in *str*[*start*:*end*] using the given + 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). The return value is the index of the first match; a value of ``-1`` indicates that no match was found, and ``-2`` indicates that an error