Unicode Type¶

These are the basic Unicode object types used for the Unicode implementation inPython:

typePy_UCS4¶

typePy_UCS2¶

typePy_UCS1¶

Part of theStable ABI.

These types are typedefs for unsigned integer types wide enough to containcharacters of 32 bits, 16 bits and 8 bits, respectively. When dealing withsingle Unicode characters, usePy_UCS4.

Added in version 3.3.

typePy_UNICODE¶

This is a typedef ofwchar_t, which is a 16-bit type or 32-bit typedepending on the platform.

Changed in version 3.3:In previous versions, this was a 16-bit type or a 32-bit type depending onwhether you selected a “narrow” or “wide” Unicode version of Python atbuild time.

Deprecated since version 3.13, will be removed in version 3.15.

typePyASCIIObject¶

typePyCompactUnicodeObject¶

typePyUnicodeObject¶

These subtypes ofPyObject represent a Python Unicode object. Inalmost all cases, they shouldn’t be used directly, since all API functionsthat deal with Unicode objects take and returnPyObject pointers.

Added in version 3.3.

PyTypeObjectPyUnicode_Type¶

Part of theStable ABI.

This instance ofPyTypeObject represents the Python Unicode type.It is exposed to Python code asstr.

PyTypeObjectPyUnicodeIter_Type¶

Part of theStable ABI.

This instance ofPyTypeObject represents the Python Unicodeiterator type. It is used to iterate over Unicode string objects.

The following APIs are C macros and static inlined functions for fast checks andaccess to internal read-only data of Unicode objects:

intPyUnicode_Check(PyObject*obj)¶

Return true if the objectobj is a Unicode object or an instance of a Unicodesubtype. This function always succeeds.

intPyUnicode_CheckExact(PyObject*obj)¶

Return true if the objectobj is a Unicode object, but not an instance of asubtype. This function always succeeds.

intPyUnicode_READY(PyObject*unicode)¶

Returns0. This API is kept only for backward compatibility.

Added in version 3.3.

Deprecated since version 3.10:This API does nothing since Python 3.12.

Py_ssize_tPyUnicode_GET_LENGTH(PyObject*unicode)¶

Return the length of the Unicode string, in code points.unicode has to be aUnicode object in the “canonical” representation (not checked).

Added in version 3.3.

Py_UCS1*PyUnicode_1BYTE_DATA(PyObject*unicode)¶

Py_UCS2*PyUnicode_2BYTE_DATA(PyObject*unicode)¶

Py_UCS4*PyUnicode_4BYTE_DATA(PyObject*unicode)¶

Return a pointer to the canonical representation cast to UCS1, UCS2 or UCS4integer types for direct character access. No checks are performed if thecanonical representation has the correct character size; usePyUnicode_KIND() to select the right function.

Added in version 3.3.

PyUnicode_1BYTE_KIND¶

PyUnicode_2BYTE_KIND¶

PyUnicode_4BYTE_KIND¶

Return values of thePyUnicode_KIND() macro.

Added in version 3.3.

Changed in version 3.12:PyUnicode_WCHAR_KIND has been removed.

intPyUnicode_KIND(PyObject*unicode)¶

Return one of the PyUnicode kind constants (see above) that indicate how manybytes per character this Unicode object uses to store its data.unicode has tobe a Unicode object in the “canonical” representation (not checked).

Added in version 3.3.

void*PyUnicode_DATA(PyObject*unicode)¶

Return a void pointer to the raw Unicode buffer.unicode has to be a Unicodeobject in the “canonical” representation (not checked).

Added in version 3.3.

voidPyUnicode_WRITE(intkind,void*data,Py_ssize_tindex,Py_UCS4value)¶

Write into a canonical representationdata (as obtained withPyUnicode_DATA()). This function performs no sanity checks, and isintended for usage in loops. The caller should cache thekind value anddata pointer as obtained from other calls.index is the index inthe string (starts at 0) andvalue is the new code point value which shouldbe written to that location.

Added in version 3.3.

Py_UCS4PyUnicode_READ(intkind,void*data,Py_ssize_tindex)¶

Read a code point from a canonical representationdata (as obtained withPyUnicode_DATA()). No checks or ready calls are performed.

Added in version 3.3.

Py_UCS4PyUnicode_READ_CHAR(PyObject*unicode,Py_ssize_tindex)¶

Read a character from a Unicode objectunicode, which must be in the “canonical”representation. This is less efficient thanPyUnicode_READ() if youdo multiple consecutive reads.

Added in version 3.3.

Py_UCS4PyUnicode_MAX_CHAR_VALUE(PyObject*unicode)¶

Return the maximum code point that is suitable for creating another stringbased onunicode, which must be in the “canonical” representation. This isalways an approximation but more efficient than iterating over the string.

Added in version 3.3.

intPyUnicode_IsIdentifier(PyObject*unicode)¶

Part of theStable ABI.

Return1 if the string is a valid identifier according to the languagedefinition, sectionIdentifiers and keywords. Return0 otherwise.

Changed in version 3.9:The function does not callPy_FatalError() anymore if the stringis not ready.

Unicode Character Properties¶

Unicode provides many different character properties. The most often needed onesare available through these macros which are mapped to C functions depending onthe Python configuration.

intPy_UNICODE_ISSPACE(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a whitespace character.

intPy_UNICODE_ISLOWER(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a lowercase character.

intPy_UNICODE_ISUPPER(Py_UCS4ch)¶

Return1 or0 depending on whetherch is an uppercase character.

intPy_UNICODE_ISTITLE(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a titlecase character.

intPy_UNICODE_ISLINEBREAK(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a linebreak character.

intPy_UNICODE_ISDECIMAL(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a decimal character.

intPy_UNICODE_ISDIGIT(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a digit character.

intPy_UNICODE_ISNUMERIC(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a numeric character.

intPy_UNICODE_ISALPHA(Py_UCS4ch)¶

Return1 or0 depending on whetherch is an alphabetic character.

intPy_UNICODE_ISALNUM(Py_UCS4ch)¶

Return1 or0 depending on whetherch is an alphanumeric character.

intPy_UNICODE_ISPRINTABLE(Py_UCS4ch)¶

Return1 or0 depending on whetherch is a printable character,in the sense ofstr.isprintable().

These APIs can be used for fast direct character conversions:

Py_UCS4Py_UNICODE_TOLOWER(Py_UCS4ch)¶

Return the characterch converted to lower case.

Py_UCS4Py_UNICODE_TOUPPER(Py_UCS4ch)¶

Return the characterch converted to upper case.

Py_UCS4Py_UNICODE_TOTITLE(Py_UCS4ch)¶

Return the characterch converted to title case.

intPy_UNICODE_TODECIMAL(Py_UCS4ch)¶

Return the characterch converted to a decimal positive integer. Return-1 if this is not possible. This function does not raise exceptions.

intPy_UNICODE_TODIGIT(Py_UCS4ch)¶

Return the characterch converted to a single digit integer. Return-1 ifthis is not possible. This function does not raise exceptions.

doublePy_UNICODE_TONUMERIC(Py_UCS4ch)¶

Return the characterch converted to a double. Return-1.0 if this is notpossible. This function does not raise exceptions.

These APIs can be used to work with surrogates:

intPy_UNICODE_IS_SURROGATE(Py_UCS4ch)¶

Check ifch is a surrogate (0xD800<=ch<=0xDFFF).

intPy_UNICODE_IS_HIGH_SURROGATE(Py_UCS4ch)¶

Check ifch is a high surrogate (0xD800<=ch<=0xDBFF).

intPy_UNICODE_IS_LOW_SURROGATE(Py_UCS4ch)¶

Check ifch is a low surrogate (0xDC00<=ch<=0xDFFF).

Py_UCS4Py_UNICODE_JOIN_SURROGATES(Py_UCS4high,Py_UCS4low)¶

Join two surrogate code points and return a singlePy_UCS4 value.high andlow are respectively the leading and trailing surrogates in asurrogate pair.high must be in the range [0xD800; 0xDBFF] andlow mustbe in the range [0xDC00; 0xDFFF].

Creating and accessing Unicode strings¶

To create Unicode objects and access their basic sequence properties, use theseAPIs:

PyObject*PyUnicode_New(Py_ssize_tsize,Py_UCS4maxchar)¶

Return value: New reference.

Create a new Unicode object.maxchar should be the true maximum code pointto be placed in the string. As an approximation, it can be rounded up to thenearest value in the sequence 127, 255, 65535, 1114111.

This is the recommended way to allocate a new Unicode object. Objectscreated using this function are not resizable.

On error, set an exception and returnNULL.

Added in version 3.3.

PyObject*PyUnicode_FromKindAndData(intkind,constvoid*buffer,Py_ssize_tsize)¶

Return value: New reference.

Create a new Unicode object with the givenkind (possible values arePyUnicode_1BYTE_KIND etc., as returned byPyUnicode_KIND()). Thebuffer must point to an array ofsizeunits of 1, 2 or 4 bytes per character, as given by the kind.

If necessary, the inputbuffer is copied and transformed into thecanonical representation. For example, if thebuffer is a UCS4 string(PyUnicode_4BYTE_KIND) and it consists only of codepoints inthe UCS1 range, it will be transformed into UCS1(PyUnicode_1BYTE_KIND).

Added in version 3.3.

PyObject*PyUnicode_FromStringAndSize(constchar*str,Py_ssize_tsize)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object from the char bufferstr. The bytes will beinterpreted as being UTF-8 encoded. The buffer is copied into the newobject.The return value might be a shared object, i.e. modification of the data isnot allowed.

This function raisesSystemError when:

• size < 0,

• str isNULL andsize > 0

Changed in version 3.12:str ==NULL withsize > 0 is not allowed anymore.

PyObject*PyUnicode_FromString(constchar*str)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object from a UTF-8 encoded null-terminated char bufferstr.

PyObject*PyUnicode_FromFormat(constchar*format,...)¶

Return value: New reference. Part of theStable ABI.

Take a Cprintf()-styleformat string and a variable number ofarguments, calculate the size of the resulting Python Unicode string and returna string with the values formatted into it. The variable arguments must be Ctypes and must correspond exactly to the format characters in theformatASCII-encoded string.

A conversion specifier contains two or more characters and has the followingcomponents, which must occur in this order:

1. The'%' character, which marks the start of the specifier.

2. Conversion flags (optional), which affect the result of some conversiontypes.

3. Minimum field width (optional).If specified as an'*' (asterisk), the actual width is given in thenext argument, which must be of typeint, and the object toconvert comes after the minimum field width and optional precision.

4. Precision (optional), given as a'.' (dot) followed by the precision.If specified as'*' (an asterisk), the actual precision is given inthe next argument, which must be of typeint, and the value toconvert comes after the precision.

5. Length modifier (optional).

6. Conversion type.

The conversion flag characters are:

Flag	Meaning
0	The conversion will be zero padded for numeric values.
-	The converted value is left adjusted (overrides the0flag if both are given).

The length modifiers for following integer conversions (d,i,o,u,x, orX) specify the type of the argument(int by default):

Modifier	Types
l	long orunsignedlong
ll	longlong orunsignedlonglong
j	intmax_t oruintmax_t
z	size_t orssize_t
t	ptrdiff_t

The length modifierl for following conversionss orV specifythat the type of the argument isconstwchar_t*.

The conversion specifiers are:

Conversion Specifier	Type	Comment
%	n/a	The literal% character.
d,i	Specified by the length modifier	The decimal representation of a signed C integer.
u	Specified by the length modifier	The decimal representation of an unsigned C integer.
o	Specified by the length modifier	The octal representation of an unsigned C integer.
x	Specified by the length modifier	The hexadecimal representation of an unsigned C integer (lowercase).
X	Specified by the length modifier	The hexadecimal representation of an unsigned C integer (uppercase).
c	int	A single character.
s	constchar* orconstwchar_t*	A null-terminated C character array.
p	constvoid*	The hex representation of a C pointer.Mostly equivalent toprintf("%p") except that it is guaranteed tostart with the literal0x regardless of what the platform’sprintf yields.
A	PyObject*	The result of callingascii().
U	PyObject*	A Unicode object.
V	PyObject*,constchar* orconstwchar_t*	A Unicode object (which may beNULL) and a null-terminatedC character array as a second parameter (which will be used,if the first parameter isNULL).
S	PyObject*	The result of callingPyObject_Str().
R	PyObject*	The result of callingPyObject_Repr().
T	PyObject*	Get the fully qualified name of an object type;callPyType_GetFullyQualifiedName().
#T	PyObject*	Similar toT format, but use a colon (:) as separator betweenthe module name and the qualified name.
N	PyTypeObject*	Get the fully qualified name of a type;callPyType_GetFullyQualifiedName().
#N	PyTypeObject*	Similar toN format, but use a colon (:) as separator betweenthe module name and the qualified name.

Note

The width formatter unit is number of characters rather than bytes.The precision formatter unit is number of bytes orwchar_titems (if the length modifierl is used) for"%s" and"%V" (if thePyObject* argument isNULL), and a number ofcharacters for"%A","%U","%S","%R" and"%V"(if thePyObject* argument is notNULL).

Note

Unlike to Cprintf() the0 flag has effect even whena precision is given for integer conversions (d,i,u,o,x, orX).

Changed in version 3.2:Support for"%lld" and"%llu" added.

Changed in version 3.3:Support for"%li","%lli" and"%zi" added.

Changed in version 3.4:Support width and precision formatter for"%s","%A","%U","%V","%S","%R" added.

Changed in version 3.12:Support for conversion specifierso andX.Support for length modifiersj andt.Length modifiers are now applied to all integer conversions.Length modifierl is now applied to conversion specifierss andV.Support for variable width and precision*.Support for flag-.

An unrecognized format character now sets aSystemError.In previous versions it caused all the rest of the format string to becopied as-is to the result string, and any extra arguments discarded.

Changed in version 3.13:Support for%T,%#T,%N and%#N formats added.

PyObject*PyUnicode_FromFormatV(constchar*format,va_listvargs)¶

Return value: New reference. Part of theStable ABI.

Identical toPyUnicode_FromFormat() except that it takes exactly twoarguments.

PyObject*PyUnicode_FromObject(PyObject*obj)¶

Return value: New reference. Part of theStable ABI.

Copy an instance of a Unicode subtype to a new true Unicode object ifnecessary. Ifobj is already a true Unicode object (not a subtype),return a newstrong reference to the object.

Objects other than Unicode or its subtypes will cause aTypeError.

PyObject*PyUnicode_FromOrdinal(intordinal)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode Object from the given Unicode code pointordinal.

The ordinal must be inrange(0x110000). AValueError israised in the case it is not.

PyObject*PyUnicode_FromEncodedObject(PyObject*obj,constchar*encoding,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Decode an encoded objectobj to a Unicode object.

bytes,bytearray and otherbytes-like objectsare decoded according to the givenencoding and using the error handlingdefined byerrors. Both can beNULL to have the interface use the defaultvalues (seeBuilt-in Codecs for details).

All other objects, including Unicode objects, cause aTypeError to beset.

The API returnsNULL if there was an error. The caller is responsible fordecref’ing the returned objects.

PyObject*PyUnicode_BuildEncodingMap(PyObject*string)¶

Return value: New reference. Part of theStable ABI.

Return a mapping suitable for decoding a custom single-byte encoding.Given a Unicode stringstring of up to 256 characters representing an encodingtable, returns either a compact internal mapping object or a dictionarymapping character ordinals to byte values. Raises aTypeError andreturnNULL on invalid input... versionadded:: 3.2

constchar*PyUnicode_GetDefaultEncoding(void)¶

Part of theStable ABI.

Return the name of the default string encoding,"utf-8".Seesys.getdefaultencoding().

The returned string does not need to be freed, and is validuntil interpreter shutdown.

Py_ssize_tPyUnicode_GetLength(PyObject*unicode)¶

Part of theStable ABI since version 3.7.

Return the length of the Unicode object, in code points.

On error, set an exception and return-1.

Added in version 3.3.

Py_ssize_tPyUnicode_CopyCharacters(PyObject*to,Py_ssize_tto_start,PyObject*from,Py_ssize_tfrom_start,Py_ssize_thow_many)¶

Copy characters from one Unicode object into another. This function performscharacter conversion when necessary and falls back tomemcpy() ifpossible. Returns-1 and sets an exception on error, otherwise returnsthe number of copied characters.

Added in version 3.3.

Py_ssize_tPyUnicode_Fill(PyObject*unicode,Py_ssize_tstart,Py_ssize_tlength,Py_UCS4fill_char)¶

Fill a string with a character: writefill_char intounicode[start:start+length].

Fail iffill_char is bigger than the string maximum character, or if thestring has more than 1 reference.

Return the number of written character, or return-1 and raise anexception on error.

Added in version 3.3.

intPyUnicode_WriteChar(PyObject*unicode,Py_ssize_tindex,Py_UCS4character)¶

Part of theStable ABI since version 3.7.

Write a character to a string. The string must have been created throughPyUnicode_New(). Since Unicode strings are supposed to be immutable,the string must not be shared, or have been hashed yet.

This function checks thatunicode is a Unicode object, that the index isnot out of bounds, and that the object can be modified safely (i.e. that itits reference count is one).

Return0 on success,-1 on error with an exception set.

Added in version 3.3.

Py_UCS4PyUnicode_ReadChar(PyObject*unicode,Py_ssize_tindex)¶

Part of theStable ABI since version 3.7.

Read a character from a string. This function checks thatunicode is aUnicode object and the index is not out of bounds, in contrast toPyUnicode_READ_CHAR(), which performs no error checking.

Return character on success,-1 on error with an exception set.

Added in version 3.3.

PyObject*PyUnicode_Substring(PyObject*unicode,Py_ssize_tstart,Py_ssize_tend)¶

Return value: New reference. Part of theStable ABI since version 3.7.

Return a substring ofunicode, from character indexstart (included) tocharacter indexend (excluded). Negative indices are not supported.On error, set an exception and returnNULL.

Added in version 3.3.

Py_UCS4*PyUnicode_AsUCS4(PyObject*unicode,Py_UCS4*buffer,Py_ssize_tbuflen,intcopy_null)¶

Part of theStable ABI since version 3.7.

Copy the stringunicode into a UCS4 buffer, including a null character, ifcopy_null is set. ReturnsNULL and sets an exception on error (inparticular, aSystemError ifbuflen is smaller than the length ofunicode).buffer is returned on success.

Added in version 3.3.

Py_UCS4*PyUnicode_AsUCS4Copy(PyObject*unicode)¶

Part of theStable ABI since version 3.7.

Copy the stringunicode into a new UCS4 buffer that is allocated usingPyMem_Malloc(). If this fails,NULL is returned with aMemoryError set. The returned buffer always has an extranull code point appended.

Added in version 3.3.

Locale Encoding¶

The current locale encoding can be used to decode text from the operatingsystem.

PyObject*PyUnicode_DecodeLocaleAndSize(constchar*str,Py_ssize_tlength,constchar*errors)¶

Return value: New reference. Part of theStable ABI since version 3.7.

Decode a string from UTF-8 on Android and VxWorks, or from the currentlocale encoding on other platforms. The supportederror handlers are"strict" and"surrogateescape"(PEP 383). The decoder uses"strict" error handler iferrors isNULL.str must end with a null character butcannot contain embedded null characters.

UsePyUnicode_DecodeFSDefaultAndSize() to decode a string fromthefilesystem encoding and error handler.

This function ignores thePython UTF-8 Mode.

See also

ThePy_DecodeLocale() function.

Added in version 3.3.

Changed in version 3.7:The function now also uses the current locale encoding for thesurrogateescape error handler, except on Android. Previously,Py_DecodeLocale()was used for thesurrogateescape, and the current locale encoding wasused forstrict.

PyObject*PyUnicode_DecodeLocale(constchar*str,constchar*errors)¶

Return value: New reference. Part of theStable ABI since version 3.7.

Similar toPyUnicode_DecodeLocaleAndSize(), but compute the stringlength usingstrlen().

Added in version 3.3.

PyObject*PyUnicode_EncodeLocale(PyObject*unicode,constchar*errors)¶

Return value: New reference. Part of theStable ABI since version 3.7.

Encode a Unicode object to UTF-8 on Android and VxWorks, or to the currentlocale encoding on other platforms. Thesupported error handlers are"strict" and"surrogateescape"(PEP 383). The encoder uses"strict" error handler iferrors isNULL. Return abytes object.unicode cannotcontain embedded null characters.

UsePyUnicode_EncodeFSDefault() to encode a string to thefilesystem encoding and error handler.

This function ignores thePython UTF-8 Mode.

See also

ThePy_EncodeLocale() function.

Added in version 3.3.

Changed in version 3.7:The function now also uses the current locale encoding for thesurrogateescape error handler, except on Android. Previously,Py_EncodeLocale()was used for thesurrogateescape, and the current locale encoding wasused forstrict.

File System Encoding¶

Functions encoding to and decoding from thefilesystem encoding anderror handler (PEP 383 andPEP 529).

To encode file names tobytes during argument parsing, the"O&"converter should be used, passingPyUnicode_FSConverter() as theconversion function:

intPyUnicode_FSConverter(PyObject*obj,void*result)¶

Part of theStable ABI.

PyArg_Parse* converter: encodestr objects – obtained directly orthrough theos.PathLike interface – tobytes usingPyUnicode_EncodeFSDefault();bytes objects are output as-is.result must be an address of a C variable of typePyObject*(orPyBytesObject*).On success, set the variable to a newstrong reference toabytes object which must be releasedwhen it is no longer used and return a non-zero value(Py_CLEANUP_SUPPORTED).Embedded null bytes are not allowed in the result.On failure, return0 with an exception set.

Ifobj isNULL, the function releases a strong referencestored in the variable referred byresult and returns1.

Added in version 3.1.

Changed in version 3.6:Accepts apath-like object.

To decode file names tostr during argument parsing, the"O&"converter should be used, passingPyUnicode_FSDecoder() as theconversion function:

intPyUnicode_FSDecoder(PyObject*obj,void*result)¶

Part of theStable ABI.

PyArg_Parse* converter: decodebytes objects – obtained eitherdirectly or indirectly through theos.PathLike interface – tostr usingPyUnicode_DecodeFSDefaultAndSize();strobjects are output as-is.result must be an address of a C variable of typePyObject*(orPyUnicodeObject*).On success, set the variable to a newstrong reference toaUnicode object which must be releasedwhen it is no longer used and return a non-zero value(Py_CLEANUP_SUPPORTED).Embedded null characters are not allowed in the result.On failure, return0 with an exception set.

Ifobj isNULL, release the strong referenceto the object referred to byresult and return1.

Added in version 3.2.

Changed in version 3.6:Accepts apath-like object.

PyObject*PyUnicode_DecodeFSDefaultAndSize(constchar*str,Py_ssize_tsize)¶

Return value: New reference. Part of theStable ABI.

Decode a string from thefilesystem encoding and error handler.

If you need to decode a string from the current locale encoding, usePyUnicode_DecodeLocaleAndSize().

See also

ThePy_DecodeLocale() function.

Changed in version 3.6:Thefilesystem error handler is now used.

PyObject*PyUnicode_DecodeFSDefault(constchar*str)¶

Return value: New reference. Part of theStable ABI.

Decode a null-terminated string from thefilesystem encoding anderror handler.

If the string length is known, usePyUnicode_DecodeFSDefaultAndSize().

Changed in version 3.6:Thefilesystem error handler is now used.

PyObject*PyUnicode_EncodeFSDefault(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object to thefilesystem encoding and errorhandler, and returnbytes. Note that the resultingbytesobject can contain null bytes.

If you need to encode a string to the current locale encoding, usePyUnicode_EncodeLocale().

See also

ThePy_EncodeLocale() function.

Added in version 3.2.

Changed in version 3.6:Thefilesystem error handler is now used.

wchar_t Support¶

wchar_t support for platforms which support it:

PyObject*PyUnicode_FromWideChar(constwchar_t*wstr,Py_ssize_tsize)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object from thewchar_t bufferwstr of the givensize.Passing-1 as thesize indicates that the function must itself compute the length,usingwcslen().ReturnNULL on failure.

Py_ssize_tPyUnicode_AsWideChar(PyObject*unicode,wchar_t*wstr,Py_ssize_tsize)¶

Part of theStable ABI.

Copy the Unicode object contents into thewchar_t bufferwstr. At mostsizewchar_t characters are copied (excluding a possibly trailingnull termination character). Return the number ofwchar_t characterscopied or-1 in case of an error.

Whenwstr isNULL, instead return thesize that would be requiredto store all ofunicode including a terminating null.

Note that the resultingwchar_t*string may or may not be null-terminated. It is the responsibility of the callerto make sure that thewchar_t* string is null-terminated in case this isrequired by the application. Also, note that thewchar_t* stringmight contain null characters, which would cause the string to be truncatedwhen used with most C functions.

wchar_t*PyUnicode_AsWideCharString(PyObject*unicode,Py_ssize_t*size)¶

Part of theStable ABI since version 3.7.

Convert the Unicode object to a wide character string. The output stringalways ends with a null character. Ifsize is notNULL, write the numberof wide characters (excluding the trailing null termination character) into*size. Note that the resultingwchar_t string might containnull characters, which would cause the string to be truncated when used withmost C functions. Ifsize isNULL and thewchar_t* stringcontains null characters aValueError is raised.

Returns a buffer allocated byPyMem_New (usePyMem_Free() to free it) on success. On error, returnsNULLand*size is undefined. Raises aMemoryError if memory allocationis failed.

Added in version 3.2.

Changed in version 3.7:Raises aValueError ifsize isNULL and thewchar_t*string contains null characters.

Generic Codecs¶

These are the generic codec APIs:

PyObject*PyUnicode_Decode(constchar*str,Py_ssize_tsize,constchar*encoding,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the encoded stringstr.encoding anderrors have the same meaning as the parameters of the same namein thestr() built-in function. The codec to be used is looked upusing the Python codec registry. ReturnNULL if an exception was raised bythe codec.

PyObject*PyUnicode_AsEncodedString(PyObject*unicode,constchar*encoding,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object and return the result as Python bytes object.encoding anderrors have the same meaning as the parameters of the samename in the Unicodeencode() method. The codec to be used is looked upusing the Python codec registry. ReturnNULL if an exception was raised bythe codec.

UTF-8 Codecs¶

These are the UTF-8 codec APIs:

PyObject*PyUnicode_DecodeUTF8(constchar*str,Py_ssize_tsize,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the UTF-8 encoded stringstr. ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_DecodeUTF8Stateful(constchar*str,Py_ssize_tsize,constchar*errors,Py_ssize_t*consumed)¶

Return value: New reference. Part of theStable ABI.

Ifconsumed isNULL, behave likePyUnicode_DecodeUTF8(). Ifconsumed is notNULL, trailing incomplete UTF-8 byte sequences will not betreated as an error. Those bytes will not be decoded and the number of bytesthat have been decoded will be stored inconsumed.

PyObject*PyUnicode_AsUTF8String(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object using UTF-8 and return the result as Python bytesobject. Error handling is “strict”. ReturnNULL if an exception wasraised by the codec.

The function fails if the string contains surrogate code points(U+D800 -U+DFFF).

constchar*PyUnicode_AsUTF8AndSize(PyObject*unicode,Py_ssize_t*size)¶

Part of theStable ABI since version 3.10.

Return a pointer to the UTF-8 encoding of the Unicode object, andstore the size of the encoded representation (in bytes) insize. Thesize argument can beNULL; in this case no size will be stored. Thereturned buffer always has an extra null byte appended (not included insize), regardless of whether there are any other null code points.

On error, set an exception, setsize to-1 (if it’s not NULL) andreturnNULL.

The function fails if the string contains surrogate code points(U+D800 -U+DFFF).

This caches the UTF-8 representation of the string in the Unicode object, andsubsequent calls will return a pointer to the same buffer. The caller is notresponsible for deallocating the buffer. The buffer is deallocated andpointers to it become invalid when the Unicode object is garbage collected.

Added in version 3.3.

Changed in version 3.7:The return type is nowconstchar* rather ofchar*.

Changed in version 3.10:This function is a part of thelimited API.

constchar*PyUnicode_AsUTF8(PyObject*unicode)¶

AsPyUnicode_AsUTF8AndSize(), but does not store the size.

Warning

This function does not have any special behavior fornull characters embedded withinunicode. As a result, strings containing null characters will remain in the returnedstring, which some C functions might interpret as the end of the string, leading totruncation. If truncation is an issue, it is recommended to usePyUnicode_AsUTF8AndSize()instead.

Added in version 3.3.

Changed in version 3.7:The return type is nowconstchar* rather ofchar*.

UTF-32 Codecs¶

These are the UTF-32 codec APIs:

PyObject*PyUnicode_DecodeUTF32(constchar*str,Py_ssize_tsize,constchar*errors,int*byteorder)¶

Return value: New reference. Part of theStable ABI.

Decodesize bytes from a UTF-32 encoded buffer string and return thecorresponding Unicode object.errors (if non-NULL) defines the errorhandling. It defaults to “strict”.

Ifbyteorder is non-NULL, the decoder starts decoding using the given byteorder:

*byteorder==-1:littleendian*byteorder==0:nativeorder*byteorder==1:bigendian

If*byteorder is zero, and the first four bytes of the input data are abyte order mark (BOM), the decoder switches to this byte order and the BOM isnot copied into the resulting Unicode string. If*byteorder is-1 or1, any byte order mark is copied to the output.

After completion,*byteorder is set to the current byte order at the endof input data.

Ifbyteorder isNULL, the codec starts in native order mode.

ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_DecodeUTF32Stateful(constchar*str,Py_ssize_tsize,constchar*errors,int*byteorder,Py_ssize_t*consumed)¶

Return value: New reference. Part of theStable ABI.

Ifconsumed isNULL, behave likePyUnicode_DecodeUTF32(). Ifconsumed is notNULL,PyUnicode_DecodeUTF32Stateful() will not treattrailing incomplete UTF-32 byte sequences (such as a number of bytes not divisibleby four) as an error. Those bytes will not be decoded and the number of bytesthat have been decoded will be stored inconsumed.

PyObject*PyUnicode_AsUTF32String(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Return a Python byte string using the UTF-32 encoding in native byteorder. The string always starts with a BOM mark. Error handling is “strict”.ReturnNULL if an exception was raised by the codec.

UTF-16 Codecs¶

These are the UTF-16 codec APIs:

PyObject*PyUnicode_DecodeUTF16(constchar*str,Py_ssize_tsize,constchar*errors,int*byteorder)¶

Return value: New reference. Part of theStable ABI.

Decodesize bytes from a UTF-16 encoded buffer string and return thecorresponding Unicode object.errors (if non-NULL) defines the errorhandling. It defaults to “strict”.

Ifbyteorder is non-NULL, the decoder starts decoding using the given byteorder:

*byteorder==-1:littleendian*byteorder==0:nativeorder*byteorder==1:bigendian

If*byteorder is zero, and the first two bytes of the input data are abyte order mark (BOM), the decoder switches to this byte order and the BOM isnot copied into the resulting Unicode string. If*byteorder is-1 or1, any byte order mark is copied to the output (where it will result ineither a\ufeff or a\ufffe character).

After completion,*byteorder is set to the current byte order at the endof input data.

Ifbyteorder isNULL, the codec starts in native order mode.

ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_DecodeUTF16Stateful(constchar*str,Py_ssize_tsize,constchar*errors,int*byteorder,Py_ssize_t*consumed)¶

Return value: New reference. Part of theStable ABI.

Ifconsumed isNULL, behave likePyUnicode_DecodeUTF16(). Ifconsumed is notNULL,PyUnicode_DecodeUTF16Stateful() will not treattrailing incomplete UTF-16 byte sequences (such as an odd number of bytes or asplit surrogate pair) as an error. Those bytes will not be decoded and thenumber of bytes that have been decoded will be stored inconsumed.

PyObject*PyUnicode_AsUTF16String(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Return a Python byte string using the UTF-16 encoding in native byteorder. The string always starts with a BOM mark. Error handling is “strict”.ReturnNULL if an exception was raised by the codec.

UTF-7 Codecs¶

These are the UTF-7 codec APIs:

PyObject*PyUnicode_DecodeUTF7(constchar*str,Py_ssize_tsize,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the UTF-7 encoded stringstr. ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_DecodeUTF7Stateful(constchar*str,Py_ssize_tsize,constchar*errors,Py_ssize_t*consumed)¶

Return value: New reference. Part of theStable ABI.

Ifconsumed isNULL, behave likePyUnicode_DecodeUTF7(). Ifconsumed is notNULL, trailing incomplete UTF-7 base-64 sections will notbe treated as an error. Those bytes will not be decoded and the number ofbytes that have been decoded will be stored inconsumed.

Unicode-Escape Codecs¶

These are the “Unicode Escape” codec APIs:

PyObject*PyUnicode_DecodeUnicodeEscape(constchar*str,Py_ssize_tsize,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the Unicode-Escape encodedstringstr. ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_AsUnicodeEscapeString(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object using Unicode-Escape and return the result as abytes object. Error handling is “strict”. ReturnNULL if an exception wasraised by the codec.

Raw-Unicode-Escape Codecs¶

These are the “Raw Unicode Escape” codec APIs:

PyObject*PyUnicode_DecodeRawUnicodeEscape(constchar*str,Py_ssize_tsize,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the Raw-Unicode-Escapeencoded stringstr. ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_AsRawUnicodeEscapeString(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object using Raw-Unicode-Escape and return the result asa bytes object. Error handling is “strict”. ReturnNULL if an exceptionwas raised by the codec.

Latin-1 Codecs¶

These are the Latin-1 codec APIs: Latin-1 corresponds to the first 256 Unicodeordinals and only these are accepted by the codecs during encoding.

PyObject*PyUnicode_DecodeLatin1(constchar*str,Py_ssize_tsize,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the Latin-1 encoded stringstr. ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_AsLatin1String(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object using Latin-1 and return the result as Python bytesobject. Error handling is “strict”. ReturnNULL if an exception wasraised by the codec.

ASCII Codecs¶

These are the ASCII codec APIs. Only 7-bit ASCII data is accepted. All othercodes generate errors.

PyObject*PyUnicode_DecodeASCII(constchar*str,Py_ssize_tsize,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the ASCII encoded stringstr. ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_AsASCIIString(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object using ASCII and return the result as Python bytesobject. Error handling is “strict”. ReturnNULL if an exception wasraised by the codec.

Character Map Codecs¶

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 codecsincluded in theencodings package). The codec uses mappings to encode anddecode characters. The mapping objects provided must support the__getitem__() mapping interface; dictionaries and sequences work well.

These are the mapping codec APIs:

PyObject*PyUnicode_DecodeCharmap(constchar*str,Py_ssize_tlength,PyObject*mapping,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Create a Unicode object by decodingsize bytes of the encoded stringstrusing the givenmapping object. ReturnNULL if an exception was raisedby the codec.

Ifmapping isNULL, Latin-1 decoding will be applied. Elsemapping must map bytes ordinals (integers in the range from 0 to 255)to Unicode strings, integers (which are then interpreted as Unicodeordinals) orNone. Unmapped data bytes – ones which cause aLookupError, as well as ones which get mapped toNone,0xFFFE or'\ufffe', are treated as undefined mappings and causean error.

PyObject*PyUnicode_AsCharmapString(PyObject*unicode,PyObject*mapping)¶

Return value: New reference. Part of theStable ABI.

Encode a Unicode object using the givenmapping object and return theresult as a bytes object. Error handling is “strict”. ReturnNULL if anexception was raised by the codec.

Themapping object must map Unicode ordinal integers to bytes objects,integers in the range from 0 to 255 orNone. Unmapped characterordinals (ones which cause aLookupError) as well as mapped toNone are treated as “undefined mapping” and cause an error.

The following codec API is special in that maps Unicode to Unicode.

PyObject*PyUnicode_Translate(PyObject*unicode,PyObject*table,constchar*errors)¶

Return value: New reference. Part of theStable ABI.

Translate a string by applying a character mapping table to it and return theresulting Unicode object. ReturnNULL if an exception was raised by thecodec.

The mapping table must map Unicode ordinal integers to Unicode ordinal integersorNone (causing deletion of the character).

Mapping tables need only provide the__getitem__() interface; dictionariesand sequences work well. Unmapped character ordinals (ones which cause aLookupError) are left untouched and are copied as-is.

errors has the usual meaning for codecs. It may beNULL which indicates touse the default error handling.

MBCS codecs for Windows¶

These are the MBCS codec APIs. They are currently only available on Windows anduse the Win32 MBCS converters to implement the conversions. Note that MBCS (orDBCS) is a class of encodings, not just one. The target encoding is defined bythe user settings on the machine running the codec.

PyObject*PyUnicode_DecodeMBCS(constchar*str,Py_ssize_tsize,constchar*errors)¶

Return value: New reference. Part of theStable ABI on Windows since version 3.7.

Create a Unicode object by decodingsize bytes of the MBCS encoded stringstr.ReturnNULL if an exception was raised by the codec.

PyObject*PyUnicode_DecodeMBCSStateful(constchar*str,Py_ssize_tsize,constchar*errors,Py_ssize_t*consumed)¶

Return value: New reference. Part of theStable ABI on Windows since version 3.7.

Ifconsumed isNULL, behave likePyUnicode_DecodeMBCS(). Ifconsumed is notNULL,PyUnicode_DecodeMBCSStateful() will not decodetrailing lead byte and the number of bytes that have been decoded will be storedinconsumed.

PyObject*PyUnicode_DecodeCodePageStateful(intcode_page,constchar*str,Py_ssize_tsize,constchar*errors,Py_ssize_t*consumed)¶

Return value: New reference. Part of theStable ABI on Windows since version 3.7.

Similar toPyUnicode_DecodeMBCSStateful(), except uses the code pagespecified bycode_page.

PyObject*PyUnicode_AsMBCSString(PyObject*unicode)¶

Return value: New reference. Part of theStable ABI on Windows since version 3.7.

Encode a Unicode object using MBCS and return the result as Python bytesobject. Error handling is “strict”. ReturnNULL if an exception wasraised by the codec.

PyObject*PyUnicode_EncodeCodePage(intcode_page,PyObject*unicode,constchar*errors)¶

Return value: New reference. Part of theStable ABI on Windows since version 3.7.

Encode the Unicode object using the specified code page and return a Pythonbytes object. ReturnNULL if an exception was raised by the codec. UseCP_ACP code page to get the MBCS encoder.

Added in version 3.3.

Methods & Slots¶