Unicode Objects
Since the implementation of
in Python 3.3, Unicode objects internally use a variety of representations, in order to allow handling the complete range of Unicode characters while staying memory efficient. There are special cases for strings where all code points are below 128, 256, or 65536; otherwise, code points must be below 1114112 (which is the full Unicode range).
UTF-8 representation is created on demand and cached in the Unicode object.
Note
The
representation has been removed since Python 3.12 with deprecated APIs. See
for more information.
Unicode Type
These are the basic Unicode object types used for the Unicode implementation in Python:
PyUnicode_Type
Part of the
.This instance of
represents the Python Unicode type. It is exposed to Python code as
.
PyUnicodeIter_Type
Part of the
.This instance of
represents the Python Unicode iterator type. It is used to iterate over Unicode string objects.
typePy_UCS4
typePy_UCS2
typePy_UCS1
Part of the
.These types are typedefs for unsigned integer types wide enough to contain characters of 32 bits, 16 bits and 8 bits, respectively. When dealing with single Unicode characters, use
.
Added in version 3.3.
typePyASCIIObject
typePyCompactUnicodeObject
typePyUnicodeObject
These subtypes of
represent a Python Unicode object. In almost all cases, they shouldn’t be used directly, since all API functions that deal with Unicode objects take and return PyObject pointers.
Added in version 3.3.
The structure of a particular object can be determined using the following macros. The macros cannot fail; their behavior is undefined if their argument is not a Python Unicode object.
PyUnicode_IS_COMPACT(o)
True if o uses the
structure.
Added in version 3.3.
PyUnicode_IS_COMPACT_ASCII(o)
True if o uses the
structure.
Added in version 3.3.
The following APIs are C macros and static inlined functions for fast checks and access to internal read-only data of Unicode objects:
intPyUnicode_Check(
*obj)
Return true if the object obj is a Unicode object or an instance of a Unicode subtype. This function always succeeds.
intPyUnicode_CheckExact(
*obj)
Return true if the object obj is a Unicode object, but not an instance of a subtype. This function always succeeds.
PyUnicode_GET_LENGTH(
*unicode)
Return the length of the Unicode string, in code points. unicode has to be a Unicode object in the “canonical” representation (not checked).
Added in version 3.3.
*PyUnicode_1BYTE_DATA(
*unicode)
*PyUnicode_2BYTE_DATA(
*unicode)
*PyUnicode_4BYTE_DATA(
*unicode)
Return a pointer to the canonical representation cast to UCS1, UCS2 or UCS4 integer types for direct character access. No checks are performed if the canonical representation has the correct character size; use
to select the right function.
Added in version 3.3.
PyUnicode_1BYTE_KIND
PyUnicode_2BYTE_KIND
PyUnicode_4BYTE_KIND
Return values of the
macro.
Added in version 3.3.
Changed in version 3.12: PyUnicode_WCHAR_KIND has been removed.
intPyUnicode_KIND(
*unicode)
Return one of the PyUnicode kind constants (see above) that indicate how many bytes per character this Unicode object uses to store its data. unicode has to be a Unicode object in the “canonical” representation (not checked).
Added in version 3.3.
void*PyUnicode_DATA(
*unicode)
Return a void pointer to the raw Unicode buffer. unicode has to be a Unicode object in the “canonical” representation (not checked).
Added in version 3.3.
voidPyUnicode_WRITE(intkind, void*data,
index,
value)
Write the code point value to the given zero-based index in a string.
The kind value and data pointer must have been obtained from a string using
and
respectively. You must hold a reference to that string while calling PyUnicode_WRITE(). All requirements of
also apply.
The function performs no checks for any of its requirements, and is intended for usage in loops.
Added in version 3.3.
PyUnicode_READ(intkind, void*data,
index)
Read a code point from a canonical representation data (as obtained with
). No checks or ready calls are performed.
Added in version 3.3.
PyUnicode_READ_CHAR(
*unicode,
index)
Read a character from a Unicode object unicode, which must be in the “canonical” representation. This is less efficient than
if you do multiple consecutive reads.
Added in version 3.3.
PyUnicode_MAX_CHAR_VALUE(
*unicode)
Return the maximum code point that is suitable for creating another string based on unicode, which must be in the “canonical” representation. This is always an approximation but more efficient than iterating over the string.
Added in version 3.3.
intPyUnicode_IsIdentifier(
*unicode)
Part of the
.Return 1 if the string is a valid identifier according to the language definition, section
Names (identifiers and keywords)
. Return 0 otherwise.
Changed in version 3.9: The function does not call
anymore if the string is not ready.
unsignedintPyUnicode_IS_ASCII(
*unicode)
Return true if the string only contains ASCII characters. Equivalent to
.
Added in version 3.2.
PyUnstable_Unicode_GET_CACHED_HASH(
*str)
This is
. It may change without warning in minor releases.
If the hash of str, as returned by
, has been cached and is immediately available, return it. Otherwise, return -1without setting an exception.
If str is not a string (that is, if PyUnicode_Check(obj) is false), the behavior is undefined.
This function never fails with an exception.
Note that there are no guarantees on when an object’s hash is cached, and the (non-)existence of a cached hash does not imply that the string has any other properties.
Unicode Character Properties
Unicode provides many different character properties. The most often needed ones are available through these macros which are mapped to C functions depending on the Python configuration.
intPy_UNICODE_ISSPACE(
ch)
Return 1 or 0 depending on whether ch is a whitespace character.
intPy_UNICODE_ISLOWER(
ch)
Return 1 or 0 depending on whether ch is a lowercase character.
intPy_UNICODE_ISUPPER(
ch)
Return 1 or 0 depending on whether ch is an uppercase character.
intPy_UNICODE_ISTITLE(
ch)
Return 1 or 0 depending on whether ch is a titlecase character.
intPy_UNICODE_ISLINEBREAK(
ch)
Return 1 or 0 depending on whether ch is a linebreak character.
intPy_UNICODE_ISDECIMAL(
ch)
Return 1 or 0 depending on whether ch is a decimal character.
intPy_UNICODE_ISDIGIT(
ch)
Return 1 or 0 depending on whether ch is a digit character.
intPy_UNICODE_ISNUMERIC(
ch)
Return 1 or 0 depending on whether ch is a numeric character.
intPy_UNICODE_ISALPHA(
ch)
Return 1 or 0 depending on whether ch is an alphabetic character.
intPy_UNICODE_ISALNUM(
ch)
Return 1 or 0 depending on whether ch is an alphanumeric character.
intPy_UNICODE_ISPRINTABLE(
ch)
Return 1 or 0 depending on whether ch is a printable character, in the sense of
.
These APIs can be used for fast direct character conversions:
Py_UNICODE_TOLOWER(
ch)
Return the character ch converted to lower case.
Py_UNICODE_TOUPPER(
ch)
Return the character ch converted to upper case.
Py_UNICODE_TOTITLE(
ch)
Return the character ch converted to title case.
intPy_UNICODE_TODECIMAL(
ch)
Return the character ch converted to a decimal positive integer. Return -1 if this is not possible. This function does not raise exceptions.
intPy_UNICODE_TODIGIT(
ch)
Return the character ch converted to a single digit integer. Return -1 if this is not possible. This function does not raise exceptions.
doublePy_UNICODE_TONUMERIC(
ch)
Return the character ch converted to a double. Return -1.0 if this is not possible. This function does not raise exceptions.
These APIs can be used to work with surrogates:
intPy_UNICODE_IS_SURROGATE(
ch)
Check if ch is a surrogate (0xD800<=ch<=0xDFFF).
intPy_UNICODE_IS_HIGH_SURROGATE(
ch)
Check if ch is a high surrogate (0xD800<=ch<=0xDBFF).
intPy_UNICODE_IS_LOW_SURROGATE(
ch)
Check if ch is a low surrogate (0xDC00<=ch<=0xDFFF).
Py_UNICODE_HIGH_SURROGATE(
ch)
Return the high UTF-16 surrogate (0xD800 to 0xDBFF) for a Unicode code point in the range [0x10000;0x10FFFF].
Py_UNICODE_LOW_SURROGATE(
ch)
Return the low UTF-16 surrogate (0xDC00 to 0xDFFF) for a Unicode code point in the range [0x10000;0x10FFFF].
Py_UNICODE_JOIN_SURROGATES(
high,
low)
Join two surrogate code points and return a single
value. high and low are respectively the leading and trailing surrogates in a surrogate pair. high must be in the range [0xD800;0xDBFF] and low must be in the range [0xDC00;0xDFFF].
Creating and accessing Unicode strings
To create Unicode objects and access their basic sequence properties, use these APIs:
*PyUnicode_New(
size,
maxchar)
Return value: New reference.Create a new Unicode object. maxchar should be the true maximum code point to be placed in the string. As an approximation, it can be rounded up to the nearest value in the sequence 127, 255, 65535, 1114111.
On error, set an exception and return NULL.
After creation, the string can be filled by
,
,
,
or similar. Since strings are supposed to be immutable, take care to not “use” the result while it is being modified. In particular, before it’s filled with its final contents, a string:
must not be hashed,
must not be
, or another non-“canonical” representation,
must not have its reference count changed,
must not be shared with code that might do one of the above.
This list is not exhaustive. Avoiding these uses is your responsibility; Python does not always check these requirements.
To avoid accidentally exposing a partially-written string object, prefer using the
API, or one of the PyUnicode_From* functions below.
Added in version 3.3.
*PyUnicode_FromKindAndData(intkind, constvoid*buffer,
size)
Return value: New reference.Create a new Unicode object with the given kind (possible values are
etc., as returned by
). The buffer must point to an array of size units of 1, 2 or 4 bytes per character, as given by the kind.
If necessary, the input buffer is copied and transformed into the canonical representation. For example, if the buffer is a UCS4 string (
) and it consists only of codepoints in the UCS1 range, it will be transformed into UCS1 (
).
Added in version 3.3.
*PyUnicode_FromStringAndSize(constchar*str,
size)
Return value: New reference. Part of the
.Create a Unicode object from the char buffer str. The bytes will be interpreted as being UTF-8 encoded. The buffer is copied into the new object. The return value might be a shared object, i.e. modification of the data is not allowed.
This function raises
when:
size < 0,
str is NULL and size > 0
Changed in version 3.12: str == NULL with size > 0 is not allowed anymore.
*PyUnicode_FromString(constchar*str)
Return value: New reference. Part of the
.Create a Unicode object from a UTF-8 encoded null-terminated char buffer str.
*PyUnicode_FromFormat(constchar*format, ...)
Return value: New reference. Part of the
.Take a C printf()-style format string and a variable number of arguments, calculate the size of the resulting Python Unicode string and return a string with the values formatted into it. The variable arguments must be C types and must correspond exactly to the format characters in the format ASCII-encoded string.
A conversion specifier contains two or more characters and has the following components, which must occur in this order:
The '%' character, which marks the start of the specifier.
Conversion flags (optional), which affect the result of some conversion types.
Minimum field width (optional). If specified as an '*' (asterisk), the actual width is given in the next argument, which must be of type int, and the object to convert comes after the minimum field width and optional precision.
Precision (optional), given as a '.' (dot) followed by the precision. If specified as '*' (an asterisk), the actual precision is given in the next argument, which must be of type int, and the value to convert comes after the precision.
Length modifier (optional).
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 the 0 flag if both are given).
The length modifiers for following integer conversions (d, i, o, u, x, or X) specify the type of the argument (int by default):
Modifier
Types
l
long or unsignedlong
ll
longlong or unsignedlonglong
j
intmax_t or uintmax_t
z
size_t or ssize_t
t
ptrdiff_t
The length modifier l for following conversions s or V specify that the type of the argument is constwchar_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* or constwchar_t*
A null-terminated C character array.
p
constvoid*
The hex representation of a C pointer. Mostly equivalent to printf("%p") except that it is guaranteed to start with the literal 0x regardless of what the platform’s printf yields.
A
*
The result of calling
.
U
*
A Unicode object.
V
*, constchar* or constwchar_t*
A Unicode object (which may be NULL) and a null-terminated C character array as a second parameter (which will be used, if the first parameter is NULL).
S
*
The result of calling
.
R
*
The result of calling
.
T
*
Get the fully qualified name of an object type; call
PyType_GetFullyQualifiedName()
.
#T
*
Similar to T format, but use a colon (:) as separator between the module name and the qualified name.
N
*
Get the fully qualified name of a type; call
PyType_GetFullyQualifiedName()
.
#N
*
Similar to N format, but use a colon (:) as separator between the 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 or wchar_t items (if the length modifier l is used) for "%s" and "%V" (if the PyObject* argument is NULL), and a number of characters for "%A", "%U", "%S", "%R" and "%V" (if the PyObject* argument is not NULL).
Note
Unlike to C printf() the 0 flag has effect even when a precision is given for integer conversions (d, i, u, o, x, or X).
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 specifiers o and X. Support for length modifiers j and t. Length modifiers are now applied to all integer conversions. Length modifier l is now applied to conversion specifiers s and V. Support for variable width and precision *. Support for flag -.
An unrecognized format character now sets a
. In previous versions it caused all the rest of the format string to be copied 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.
*PyUnicode_FromFormatV(constchar*format, va_listvargs)
Return value: New reference. Part of the
.Identical to
except that it takes exactly two arguments.
*PyUnicode_FromObject(
*obj)
Return value: New reference. Part of the
.Copy an instance of a Unicode subtype to a new true Unicode object if necessary. If obj is already a true Unicode object (not a subtype), return a new
to the object.
Objects other than Unicode or its subtypes will cause a
.
*PyUnicode_FromOrdinal(intordinal)
Return value: New reference. Part of the
.Create a Unicode Object from the given Unicode code point ordinal.
The ordinal must be in range(0x110000). A
is raised in the case it is not.
*PyUnicode_FromEncodedObject(
*obj, constchar*encoding, constchar*errors)
Return value: New reference. Part of the
.Decode an encoded object obj to a Unicode object.
,
and other
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
for details).
All other objects, including Unicode objects, cause a
to be set.
The API returns NULL if there was an error. The caller is responsible for decref’ing the returned objects.
voidPyUnicode_Append(
**p_left,
*right)
Part of the
.Append the string right to the end of p_left. p_left must point to a
to a Unicode object; PyUnicode_Append() releases (”
”) this reference.
On error, set *p_left to NULL and set an exception.
On success, set *p_left to a new strong reference to the result.
voidPyUnicode_AppendAndDel(
**p_left,
*right)
Part of the
.The function is similar to
, with the only difference being that it decrements the reference count of right by one.
*PyUnicode_BuildEncodingMap(
*string)
Return value: New reference. Part of the
.Return a mapping suitable for decoding a custom single-byte encoding. Given a Unicode string string of up to 256 characters representing an encoding table, returns either a compact internal mapping object or a dictionary mapping character ordinals to byte values. Raises a
and return NULL on invalid input.
Added in version 3.2.
constchar*PyUnicode_GetDefaultEncoding(void)
Part of the
.Return the name of the default string encoding, "utf-8". See
.
The returned string does not need to be freed, and is valid until interpreter shutdown.
PyUnicode_GetLength(
*unicode)
Part of the
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.
PyUnicode_CopyCharacters(
*to,
to_start,
*from,
from_start,
how_many)
Copy characters from one Unicode object into another. This function performs character conversion when necessary and falls back to memcpy() if possible. Returns -1 and sets an exception on error, otherwise returns the number of copied characters.
The string must not have been “used” yet. See
for details.
Added in version 3.3.
intPyUnicode_Resize(
**unicode,
length);
Part of the
.Resize a Unicode object *unicode to the new length in code points.
Try to resize the string in place (which is usually faster than allocating a new string and copying characters), or create a new string.
*unicode is modified to point to the new (resized) object and 0 is returned on success. Otherwise, -1 is returned and an exception is set, and *unicode is left untouched.
The function doesn’t check string content, the result may not be a string in canonical representation.
PyUnicode_Fill(
*unicode,
start,
length,
fill_char)
Fill a string with a character: write fill_char into unicode[start:start+length].
Fail if fill_char is bigger than the string maximum character, or if the string has more than 1 reference.
The string must not have been “used” yet. See
for details.
Return the number of written characters, or return -1 and raise an exception on error.
Added in version 3.3.
intPyUnicode_WriteChar(
*unicode,
index,
character)
Part of the
since version 3.7.Write a character to the string unicode at the zero-based index. Return 0 on success, -1 on error with an exception set.
This function checks that unicode is a Unicode object, that the index is not out of bounds, and that the object’s reference count is one. See
for a version that skips these checks, making them your responsibility.
The string must not have been “used” yet. See
for details.
Added in version 3.3.
PyUnicode_ReadChar(
*unicode,
index)
Part of the
since version 3.7.Read a character from a string. This function checks that unicode is a Unicode object and the index is not out of bounds, in contrast to
, which performs no error checking.
Return character on success, -1 on error with an exception set.
Added in version 3.3.
*PyUnicode_Substring(
*unicode,
start,
end)
Return value: New reference. Part of the
since version 3.7.Return a substring of unicode, from character index start (included) to character index end (excluded). Negative indices are not supported. On error, set an exception and return NULL.
Added in version 3.3.
*PyUnicode_AsUCS4(
*unicode,
*buffer,
buflen, intcopy_null)
Part of the
since version 3.7.Copy the string unicode into a UCS4 buffer, including a null character, if copy_null is set. Returns NULL and sets an exception on error (in particular, a
if buflen is smaller than the length of unicode). buffer is returned on success.
Added in version 3.3.
*PyUnicode_AsUCS4Copy(
*unicode)
Part of the
since version 3.7.Copy the string unicode into a new UCS4 buffer that is allocated using
. If this fails, NULL is returned with a
set. The returned buffer always has an extra null code point appended.
Added in version 3.3.
Locale Encoding
The current locale encoding can be used to decode text from the operating system.
*PyUnicode_DecodeLocaleAndSize(constchar*str,
length, constchar*errors)
Return value: New reference. Part of the
since version 3.7.Decode a string from UTF-8 on Android and VxWorks, or from the current locale encoding on other platforms. The supported error handlers are "strict" and "surrogateescape" (
). The decoder uses "strict" error handler if errors is NULL. str must end with a null character but cannot contain embedded null characters.
Use
PyUnicode_DecodeFSDefaultAndSize()
to decode a string from the
filesystem encoding and error handler
.
This function ignores the
.
Added in version 3.3.
Changed in version 3.7: The function now also uses the current locale encoding for the surrogateescape error handler, except on Android. Previously,
was used for the surrogateescape, and the current locale encoding was used for strict.
*PyUnicode_DecodeLocale(constchar*str, constchar*errors)
Return value: New reference. Part of the
since version 3.7.Similar to
PyUnicode_DecodeLocaleAndSize()
, but compute the string length using strlen().
Added in version 3.3.
*PyUnicode_EncodeLocale(
*unicode, constchar*errors)
Return value: New reference. Part of the
since version 3.7.Encode a Unicode object to UTF-8 on Android and VxWorks, or to the current locale encoding on other platforms. The supported error handlers are "strict" and "surrogateescape" (
). The encoder uses "strict" error handler if errors is NULL. Return a
object. unicode cannot contain embedded null characters.
Use
to encode a string to the
filesystem encoding and error handler
.
This function ignores the
.
Added in version 3.3.
Changed in version 3.7: The function now also uses the current locale encoding for the surrogateescape error handler, except on Android. Previously,
was used for the surrogateescape, and the current locale encoding was used for strict.
File System Encoding
Functions encoding to and decoding from the
filesystem encoding and error handler
(
and
).
To encode file names to
during argument parsing, the "O&" converter should be used, passing PyUnicode_FSConverter() as the conversion function:
intPyUnicode_FSConverter(
*obj, void*result)
Part of the
.
: encode
objects – obtained directly or through the
interface – to
using
; bytes objects are output as-is. result must be an address of a C variable of type
* (or
*). On success, set the variable to a new
to a
which must be released when it is no longer used and return a non-zero value (
). Embedded null bytes are not allowed in the result. On failure, return 0 with an exception set.
If obj is NULL, the function releases a strong reference stored in the variable referred by result and returns 1.
Added in version 3.1.
To decode file names to
during argument parsing, the "O&" converter should be used, passing PyUnicode_FSDecoder() as the conversion function:
intPyUnicode_FSDecoder(
*obj, void*result)
Part of the
.
: decode
objects – obtained either directly or indirectly through the
interface – to
using
PyUnicode_DecodeFSDefaultAndSize()
; str objects are output as-is. result must be an address of a C variable of type
* (or
*). On success, set the variable to a new
to a
which must be released when it is no longer used and return a non-zero value (
). Embedded null characters are not allowed in the result. On failure, return 0 with an exception set.
If obj is NULL, release the strong reference to the object referred to by result and return 1.
Added in version 3.2.
*PyUnicode_DecodeFSDefaultAndSize(constchar*str,
size)
Return value: New reference. Part of the
.Decode a string from the
filesystem encoding and error handler
.
If you need to decode a string from the current locale encoding, use
PyUnicode_DecodeLocaleAndSize()
.
*PyUnicode_DecodeFSDefault(constchar*str)
Return value: New reference. Part of the
.Decode a null-terminated string from the
filesystem encoding and error handler
.
If the string length is known, use
PyUnicode_DecodeFSDefaultAndSize()
.
*PyUnicode_EncodeFSDefault(
*unicode)
Return value: New reference. Part of the
.Encode a Unicode object to the
filesystem encoding and error handler
, and return
. Note that the resulting bytes object can contain null bytes.
If you need to encode a string to the current locale encoding, use
.
Added in version 3.2.
wchar_t Support
wchar_t support for platforms which support it:
*PyUnicode_FromWideChar(constwchar_t*wstr,
size)
Return value: New reference. Part of the
.Create a Unicode object from the wchar_t buffer wstr of the given size. Passing -1 as the size indicates that the function must itself compute the length, using wcslen(). Return NULL on failure.
PyUnicode_AsWideChar(
*unicode, wchar_t*wstr,
size)
Part of the
.Copy the Unicode object contents into the wchar_t buffer wstr. At most sizewchar_t characters are copied (excluding a possibly trailing null termination character). Return the number of wchar_t characters copied or -1 in case of an error.
When wstr is NULL, instead return the size that would be required to store all of unicode including a terminating null.
Note that the resulting wchar_t* string may or may not be null-terminated. It is the responsibility of the caller to make sure that the wchar_t* string is null-terminated in case this is required by the application. Also, note that the wchar_t* string might contain null characters, which would cause the string to be truncated when used with most C functions.
wchar_t*PyUnicode_AsWideCharString(
*unicode,
*size)
Part of the
since version 3.7.Convert the Unicode object to a wide character string. The output string always ends with a null character. If size is not NULL, write the number of wide characters (excluding the trailing null termination character) into *size. Note that the resulting wchar_t string might contain null characters, which would cause the string to be truncated when used with most C functions. If size is NULL and the wchar_t* string contains null characters a
is raised.
Returns a buffer allocated by
(use
to free it) on success. On error, returns NULL and *size is undefined. Raises a
if memory allocation is failed.
Added in version 3.2.
Changed in version 3.7: Raises a
if size is NULL and the wchar_t* string contains null characters.
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, and they have the same semantics as the ones of the built-in
string object constructor.
Setting encoding to NULL causes the default encoding to be used which is UTF-8. The file system calls should use
for encoding file names. This uses the
filesystem encoding and error handler
internally.
Error handling is set by errors which may also be set to NULL meaning to use the default handling defined for the codec. Default error handling for all built-in codecs is “strict” (
is raised).
The codecs all use a similar interface. Only deviations from the following generic ones are documented for simplicity.
Generic Codecs
The following macro is provided:
Py_UNICODE_REPLACEMENT_CHARACTER
The Unicode code point U+FFFD (replacement character).
This Unicode character is used as the replacement character during decoding if the errors argument is set to “replace”.
These are the generic codec APIs:
*PyUnicode_Decode(constchar*str,
size, constchar*encoding, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the encoded string str. encoding and errors have the same meaning as the parameters of the same name in the
built-in function. The codec to be used is looked up using the Python codec registry. Return NULL if an exception was raised by the codec.
*PyUnicode_AsEncodedString(
*unicode, constchar*encoding, constchar*errors)
Return value: New reference. Part of the
.Encode a Unicode object and return the result as Python bytes object. encoding and errors have the same meaning as the parameters of the same name in the Unicode
method. The codec to be used is looked up using the Python codec registry. Return NULL if an exception was raised by the codec.
UTF-8 Codecs
These are the UTF-8 codec APIs:
*PyUnicode_DecodeUTF8(constchar*str,
size, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the UTF-8 encoded string str. Return NULL if an exception was raised by the codec.
*PyUnicode_DecodeUTF8Stateful(constchar*str,
size, constchar*errors,
*consumed)
Return value: New reference. Part of the
.If consumed is NULL, behave like
. If consumed is not NULL, trailing incomplete UTF-8 byte sequences will not be treated as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed.
*PyUnicode_AsUTF8String(
*unicode)
Return value: New reference. Part of the
.Encode a Unicode object using UTF-8 and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.
The function fails if the string contains surrogate code points (U+D800 - U+DFFF).
constchar*PyUnicode_AsUTF8AndSize(
*unicode,
*size)
Part of the
since version 3.10.Return a pointer to the UTF-8 encoding of the Unicode object, and store the size of the encoded representation (in bytes) in size. The size argument can be NULL; in this case no size will be stored. The returned buffer always has an extra null byte appended (not included in size), regardless of whether there are any other null code points.
On error, set an exception, set size to -1 (if it’s not NULL) and return NULL.
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, and subsequent calls will return a pointer to the same buffer. The caller is not responsible for deallocating the buffer. The buffer is deallocated and pointers 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 now constchar* rather than char*.
Changed in version 3.10: This function is a part of the
.
constchar*PyUnicode_AsUTF8(
*unicode)
As
, but does not store the size.
Warning
This function does not have any special behavior for
embedded within unicode. As a result, strings containing null characters will remain in the returned string, which some C functions might interpret as the end of the string, leading to truncation. If truncation is an issue, it is recommended to use
instead.
Added in version 3.3.
Changed in version 3.7: The return type is now constchar* rather than char*.
UTF-32 Codecs
These are the UTF-32 codec APIs:
*PyUnicode_DecodeUTF32(constchar*str,
size, constchar*errors, int*byteorder)
Return value: New reference. Part of 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”.
If byteorder is non-NULL, the decoder starts decoding using the given byte order:
*byteorder==-1:littleendian*byteorder==0:nativeorder*byteorder==1:bigendianIf *byteorder is zero, and the first four bytes of the input data are a byte order mark (BOM), the decoder switches to this byte order and the BOM is not copied into the resulting Unicode string. If *byteorder is -1 or 1, any byte order mark is copied to the output.
After completion, *byteorder is set to the current byte order at the end of input data.
If byteorder is NULL, the codec starts in native order mode.
Return NULL if an exception was raised by the codec.
*PyUnicode_DecodeUTF32Stateful(constchar*str,
size, constchar*errors, int*byteorder,
*consumed)
Return value: New reference. Part of the
.If consumed is NULL, behave like
. If consumed is not NULL,
PyUnicode_DecodeUTF32Stateful()
will not treat trailing incomplete UTF-32 byte sequences (such as a number of bytes not divisible by four) as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed.
*PyUnicode_AsUTF32String(
*unicode)
Return value: New reference. Part of the
.Return a Python byte string using the UTF-32 encoding in native byte order. The string always starts with a BOM mark. Error handling is “strict”. Return NULL if an exception was raised by the codec.
UTF-16 Codecs
These are the UTF-16 codec APIs:
*PyUnicode_DecodeUTF16(constchar*str,
size, constchar*errors, int*byteorder)
Return value: New reference. Part of 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”.
If byteorder is non-NULL, the decoder starts decoding using the given byte order:
*byteorder==-1:littleendian*byteorder==0:nativeorder*byteorder==1:bigendianIf *byteorder is zero, and the first two bytes of the input data are a byte order mark (BOM), the decoder switches to this byte order and the BOM is not copied into the resulting Unicode string. If *byteorder is -1 or 1, any byte order mark is copied to the output (where it will result in either a \ufeff or a \ufffe character).
After completion, *byteorder is set to the current byte order at the end of input data.
If byteorder is NULL, the codec starts in native order mode.
Return NULL if an exception was raised by the codec.
*PyUnicode_DecodeUTF16Stateful(constchar*str,
size, constchar*errors, int*byteorder,
*consumed)
Return value: New reference. Part of the
.If consumed is NULL, behave like
. If consumed is not NULL,
PyUnicode_DecodeUTF16Stateful()
will not treat trailing incomplete UTF-16 byte sequences (such as an odd number of bytes or a split surrogate pair) as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed.
*PyUnicode_AsUTF16String(
*unicode)
Return value: New reference. Part of the
.Return a Python byte string using the UTF-16 encoding in native byte order. The string always starts with a BOM mark. Error handling is “strict”. Return NULL if an exception was raised by the codec.
UTF-7 Codecs
These are the UTF-7 codec APIs:
*PyUnicode_DecodeUTF7(constchar*str,
size, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the UTF-7 encoded string str. Return NULL if an exception was raised by the codec.
*PyUnicode_DecodeUTF7Stateful(constchar*str,
size, constchar*errors,
*consumed)
Return value: New reference. Part of the
.If consumed is NULL, behave like
. If consumed is not NULL, trailing incomplete UTF-7 base-64 sections will not be treated as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed.
Unicode-Escape Codecs
These are the “Unicode Escape” codec APIs:
*PyUnicode_DecodeUnicodeEscape(constchar*str,
size, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the Unicode-Escape encoded string str. Return NULL if an exception was raised by the codec.
*PyUnicode_AsUnicodeEscapeString(
*unicode)
Return value: New reference. Part of the
.Encode a Unicode object using Unicode-Escape and return the result as a bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.
Raw-Unicode-Escape Codecs
These are the “Raw Unicode Escape” codec APIs:
*PyUnicode_DecodeRawUnicodeEscape(constchar*str,
size, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the Raw-Unicode-Escape encoded string str. Return NULL if an exception was raised by the codec.
*PyUnicode_AsRawUnicodeEscapeString(
*unicode)
Return value: New reference. Part of the
.Encode a Unicode object using Raw-Unicode-Escape and return the result as a bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.
Latin-1 Codecs
These are the Latin-1 codec APIs: Latin-1 corresponds to the first 256 Unicode ordinals and only these are accepted by the codecs during encoding.
*PyUnicode_DecodeLatin1(constchar*str,
size, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the Latin-1 encoded string str. Return NULL if an exception was raised by the codec.
*PyUnicode_AsLatin1String(
*unicode)
Return value: New reference. Part of the
.Encode a Unicode object using Latin-1 and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.
ASCII Codecs
These are the ASCII codec APIs. Only 7-bit ASCII data is accepted. All other codes generate errors.
*PyUnicode_DecodeASCII(constchar*str,
size, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the ASCII encoded string str. Return NULL if an exception was raised by the codec.
*PyUnicode_AsASCIIString(
*unicode)
Return value: New reference. Part of the
.Encode a Unicode object using ASCII and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised 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 codecs included in the encodings package). The codec uses mappings to encode and decode characters. The mapping objects provided must support the
mapping interface; dictionaries and sequences work well.
These are the mapping codec APIs:
*PyUnicode_DecodeCharmap(constchar*str,
length,
*mapping, constchar*errors)
Return value: New reference. Part of the
.Create a Unicode object by decoding size bytes of the encoded string str using the given mapping object. Return NULL if an exception was raised by the codec.
If mapping is NULL, Latin-1 decoding will be applied. Else mapping must map bytes ordinals (integers in the range from 0 to 255) to Unicode strings, integers (which are then interpreted as Unicode ordinals) or None. Unmapped data bytes – ones which cause a
, as well as ones which get mapped to None, 0xFFFE or '\ufffe', are treated as undefined mappings and cause an error.
*PyUnicode_AsCharmapString(
*unicode,
*mapping)
Return value: New reference. Part of the
.Encode a Unicode object using the given mapping object and return the result as a bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.
The mapping object must map Unicode ordinal integers to bytes objects, integers in the range from 0 to 255 or None. Unmapped character ordinals (ones which cause a
) as well as mapped to None are treated as “undefined mapping” and cause an error.
The following codec API is special in that maps Unicode to Unicode.
*PyUnicode_Translate(
*unicode,
*table, constchar*errors)
Return value: New reference. Part of the
.Translate a string by applying a character mapping table to it and return the resulting Unicode object. Return NULL if an exception was raised by the codec.
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
interface; dictionaries and sequences work well. Unmapped character ordinals (ones which cause a
) 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.
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.
*PyUnicode_DecodeMBCS(constchar*str,
size, constchar*errors)
Return value: New reference. Part of the
on Windows since version 3.7.Create a Unicode object by decoding size bytes of the MBCS encoded string str. Return NULL if an exception was raised by the codec.
*PyUnicode_DecodeMBCSStateful(constchar*str,
size, constchar*errors,
*consumed)
Return value: New reference. Part of the
on Windows since version 3.7.If consumed is NULL, behave like
. If consumed is not NULL,
PyUnicode_DecodeMBCSStateful()
will not decode trailing lead byte and the number of bytes that have been decoded will be stored in consumed.
*PyUnicode_DecodeCodePageStateful(intcode_page, constchar*str,
size, constchar*errors,
*consumed)
Return value: New reference. Part of the
on Windows since version 3.7.Similar to
PyUnicode_DecodeMBCSStateful()
, except uses the code page specified by code_page.
*PyUnicode_AsMBCSString(
*unicode)
Return value: New reference. Part of the
on Windows since version 3.7.Encode a Unicode object using MBCS and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.
*PyUnicode_EncodeCodePage(intcode_page,
*unicode, constchar*errors)
Return value: New reference. Part of the
on Windows since version 3.7.Encode the Unicode object using the specified code page and return a Python bytes object. Return NULL if an exception was raised by the codec. Use CP_ACP code page to get the MBCS encoder.
Added in version 3.3.
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 appropriate.
They all return NULL or -1 if an exception occurs.
*PyUnicode_Concat(
*left,
*right)
Return value: New reference. Part of the
.Concat two strings giving a new Unicode string.
*PyUnicode_Split(
*unicode,
*sep,
maxsplit)
Return value: New reference. Part of the
.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.
On error, return NULL with an exception set.
Equivalent to
.
*PyUnicode_RSplit(
*unicode,
*sep,
maxsplit)
Return value: New reference. Part of the
.Similar to
, but splitting will be done beginning at the end of the string.
On error, return NULL with an exception set.
Equivalent to
.
*PyUnicode_Splitlines(
*unicode, intkeepends)
Return value: New reference. Part of the
.Split a Unicode string at line breaks, returning a list of Unicode strings. CRLF is considered to be one line break. If keepends is 0, the Line break characters are not included in the resulting strings.
*PyUnicode_Partition(
*unicode,
*sep)
Return value: New reference. Part of the
.Split a Unicode string at the first occurrence of sep, and return a 3-tuple containing the part before the separator, the separator itself, and the part after the separator. If the separator is not found, return a 3-tuple containing the string itself, followed by two empty strings.
sep must not be empty.
On error, return NULL with an exception set.
Equivalent to
.
*PyUnicode_RPartition(
*unicode,
*sep)
Return value: New reference. Part of the
.Similar to
, but split a Unicode string at the last occurrence of sep. If the separator is not found, return a 3-tuple containing two empty strings, followed by the string itself.
sep must not be empty.
On error, return NULL with an exception set.
Equivalent to
.
*PyUnicode_Join(
*separator,
*seq)
Return value: New reference. Part of the
.Join a sequence of strings using the given separator and return the resulting Unicode string.
PyUnicode_Tailmatch(
*unicode,
*substr,
start,
end, intdirection)
Part of the
.Return 1 if substr matches unicode[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.
PyUnicode_Find(
*unicode,
*substr,
start,
end, intdirection)
Part of the
.Return the first position of substr in unicode[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 occurred and an exception has been set.
PyUnicode_FindChar(
*unicode,
ch,
start,
end, intdirection)
Part of the
since version 3.7.Return the first position of the character ch in unicode[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 occurred and an exception has been set.
Added in version 3.3.
Changed in version 3.7: start and end are now adjusted to behave like unicode[start:end].
PyUnicode_Count(
*unicode,
*substr,
start,
end)
Part of the
.Return the number of non-overlapping occurrences of substr in unicode[start:end]. Return -1 if an error occurred.
*PyUnicode_Replace(
*unicode,
*substr,
*replstr,
maxcount)
Return value: New reference. Part of the
.Replace at most maxcount occurrences of substr in unicode with replstr and return the resulting Unicode object. maxcount == -1 means replace all occurrences.
intPyUnicode_Compare(
*left,
*right)
Part of the
.Compare two strings and return -1, 0, 1 for less than, equal, and greater than, respectively.
This function returns -1 upon failure, so one should call
to check for errors.
See also
The
function.
intPyUnicode_Equal(
*a,
*b)
Part of the
since version 3.14.Test if two strings are equal:
Return 1 if a is equal to b.
Return 0 if a is not equal to b.
Set a
exception and return -1 if a or b is not a
object.
The function always succeeds if a and b are
objects.
The function works for
subclasses, but does not honor custom __eq__() method.
See also
The
function.
Added in version 3.14.
intPyUnicode_EqualToUTF8AndSize(
*unicode, constchar*string,
size)
Part of the
since version 3.13.Compare a Unicode object with a char buffer which is interpreted as being UTF-8 or ASCII encoded and return true (1) if they are equal, or false (0) otherwise. If the Unicode object contains surrogate code points (U+D800 - U+DFFF) or the C string is not valid UTF-8, false (0) is returned.
This function does not raise exceptions.
Added in version 3.13.
intPyUnicode_EqualToUTF8(
*unicode, constchar*string)
Part of the
since version 3.13.Similar to
PyUnicode_EqualToUTF8AndSize()
, but compute string length using strlen(). If the Unicode object contains null characters, false (0) is returned.
Added in version 3.13.
intPyUnicode_CompareWithASCIIString(
*unicode, constchar*string)
Part of the
.Compare a Unicode object, unicode, with string and return -1, 0, 1 for less than, equal, and greater than, respectively. It is best to pass only ASCII-encoded strings, but the function interprets the input string as ISO-8859-1 if it contains non-ASCII characters.
This function does not raise exceptions.
*PyUnicode_RichCompare(
*left,
*right, intop)
Return value: New reference. Part of the
.Rich compare two Unicode strings and return one of the following:
NULL in case an exception was raised
or
for successful comparisons
in case the type combination is unknown
Possible values for op are
,
,
,
,
, and
.
*PyUnicode_Format(
*format,
*args)
Return value: New reference. Part of the
.Return a new string object from format and args; this is analogous to format%args.
intPyUnicode_Contains(
*unicode,
*substr)
Part of the
.Check whether substr is contained in unicode and return true or false accordingly.
substr has to coerce to a one element Unicode string. -1 is returned if there was an error.
voidPyUnicode_InternInPlace(
**p_unicode)
Part of the
.Intern the argument *
in place. The argument must be the address of a pointer variable pointing to a Python Unicode string object. If there is an existing interned string that is the same as *p_unicode, it sets *p_unicode to it (releasing the reference to the old string object and creating a new
to the interned string object), otherwise it leaves *p_unicode alone and interns it.
(Clarification: even though there is a lot of talk about references, think of this function as reference-neutral. You must own the object you pass in; after the call you no longer own the passed-in reference, but you newly own the result.)
This function never raises an exception. On error, it leaves its argument unchanged without interning it.
Instances of subclasses of
may not be interned, that is,
(*
) must be true. If it is not, then – as with any other error – the argument is left unchanged.
Note that interned strings are not “immortal”. You must keep a reference to the result to benefit from interning.
*PyUnicode_InternFromString(constchar*str)
Return value: New reference. Part of the
.A combination of
and
, meant for statically allocated strings.
Return a new (“owned”) reference to either a new Unicode string object that has been interned, or an earlier interned string object with the same value.
Python may keep a reference to the result, or make it
, preventing it from being garbage-collected promptly. For interning an unbounded number of different strings, such as ones coming from user input, prefer calling
and
directly.
unsignedintPyUnicode_CHECK_INTERNED(
*str)
Return a non-zero value if str is interned, zero if not. The str argument must be a string; this is not checked. This function always succeeds.
CPython implementation detail: A non-zero return value may carry additional information about how the string is interned. The meaning of such non-zero values, as well as each specific string’s intern-related details, may change between CPython versions.
PyUnicodeWriter
The
API can be used to create a Python
object.
Added in version 3.14.
typePyUnicodeWriter
A Unicode writer instance.
The instance must be destroyed by
on success, or
on error.
*PyUnicodeWriter_Create(
length)
Create a Unicode writer instance.
length must be greater than or equal to 0.
If length is greater than 0, preallocate an internal buffer of length characters.
Set an exception and return NULL on error.
*PyUnicodeWriter_Finish(
*writer)
Return the final Python
object and destroy the writer instance.
Set an exception and return NULL on error.
The writer instance is invalid after this call.
voidPyUnicodeWriter_Discard(
*writer)
Discard the internal Unicode buffer and destroy the writer instance.
If writer is NULL, no operation is performed.
The writer instance is invalid after this call.
intPyUnicodeWriter_WriteChar(
*writer,
ch)
Write the single Unicode character ch into writer.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
intPyUnicodeWriter_WriteUTF8(
*writer, constchar*str,
size)
Decode the string str from UTF-8 in strict mode and write the output into writer.
size is the string length in bytes. If size is equal to -1, call strlen(str) to get the string length.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
See also
PyUnicodeWriter_DecodeUTF8Stateful()
.
intPyUnicodeWriter_WriteASCII(
*writer, constchar*str,
size)
Write the ASCII string str into writer.
size is the string length in bytes. If size is equal to -1, call strlen(str) to get the string length.
str must only contain ASCII characters. The behavior is undefined if str contains non-ASCII characters.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
intPyUnicodeWriter_WriteWideChar(
*writer, constwchar_t*str,
size)
Write the wide string str into writer.
size is a number of wide characters. If size is equal to -1, call wcslen(str) to get the string length.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
intPyUnicodeWriter_WriteUCS4(
*writer, const
*str,
size)
Writer the UCS4 string str into writer.
size is a number of UCS4 characters.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
intPyUnicodeWriter_WriteStr(
*writer,
*obj)
Call
on obj and write the output into writer.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
To write a
subclass which overrides the
method,
can be used to get the original string.
intPyUnicodeWriter_WriteRepr(
*writer,
*obj)
Call
on obj and write the output into writer.
If obj is NULL, write the string "<NULL>" into writer.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
Changed in version 3.14.4: Added support for NULL.
intPyUnicodeWriter_WriteSubstring(
*writer,
*str,
start,
end)
Write the substring str[start:end] into writer.
str must be Python
object. start must be greater than or equal to 0, and less than or equal to end. end must be less than or equal to str length.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
intPyUnicodeWriter_Format(
*writer, constchar*format, ...)
Similar to
, but write the output directly into writer.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
intPyUnicodeWriter_DecodeUTF8Stateful(
*writer, constchar*string,
length, constchar*errors,
*consumed)
Decode the string str from UTF-8 with errors error handler and write the output into writer.
size is the string length in bytes. If size is equal to -1, call strlen(str) to get the string length.
errors is an
name, such as "replace". If errors is NULL, use the strict error handler.
If consumed is not NULL, set *consumed to the number of decoded bytes on success. If consumed is NULL, treat trailing incomplete UTF-8 byte sequences as an error.
On success, return 0. On error, set an exception, leave the writer unchanged, and return -1.
See also
.
Deprecated API
The following API is deprecated.
typePy_UNICODE
This is a typedef of wchar_t, which is a 16-bit type or 32-bit type depending on the platform. Please use wchar_t directly instead.
Changed in version 3.3: In previous versions, this was a 16-bit type or a 32-bit type depending on whether you selected a “narrow” or “wide” Unicode version of Python at build time.
Deprecated since version 3.13, removed in version 3.16.
intPyUnicode_READY(
*unicode)
Do nothing and return 0. This API is kept only for backward compatibility, but there are no plans to remove it.
Added in version 3.3.
Deprecated since version 3.10: This API does nothing since Python 3.12. Previously, this needed to be called for each string created using the old API (PyUnicode_FromUnicode() or similar).
unsignedintPyUnicode_IS_READY(
*unicode)
Do nothing and return 1. This API is kept only for backward compatibility, but there are no plans to remove it.
Added in version 3.3.
Deprecated since version 3.14: This API does nothing since Python 3.12. Previously, this could be called to check if
is necessary.