In reviewing bpo-13604 (aligning PEP-393 with the implementation) Victor Stinner noticed that PyUnicode_AsUnicodeAndSize is new in 3.3, but that it is already deprecated (because it relies on the old PyUnicode type).

This born-deprecated function is just a shortcut for PyUnicode_AsUnicode plus PyUnicode_GET_SIZE, and should be removed.

It is now a useful function, as PyUnicode_AsUnicode defers to it.

It is still born-deprecated, but that may be unavoidable, as all use of the wstr format is deprecated.

It could be made an internal function.

The Py_UNICODE* type is deprecated but since Python 3.3, Py_UNICODE=wchar_t and wchar_t* is a common type on Windows. PyUnicode_AsUnicodeAndSize() is used to encode Python strings to call Windows functions.

PyUnicode_AsUnicodeAndSize() is preferred over PyUnicode_AsWideCharString() because PyUnicode_AsWideCharString() stores the result in the Unicode string and the Unicode string releases the memory automatically later. Calling PyUnicode_AsWideCharString() twice on the same string avoids also the need of encoding the string twice because the result is cached.

I proposed to add a new function using wchar_*t and storing the result in the Unicode string, but the idea was rejected. I don't remember why.

STINNER Victor wrote:

STINNER Victor <victor.stinner@gmail.com> added the comment:

The Py_UNICODE* type is deprecated but since Python 3.3, Py_UNICODE=wchar_t and wchar_t* is a common type on Windows. PyUnicode_AsUnicodeAndSize() is used to encode Python strings to call Windows functions.

PyUnicode_AsUnicodeAndSize() is preferred over PyUnicode_AsWideCharString() because PyUnicode_AsWideCharString() stores the result in the Unicode string and the Unicode string releases the memory automatically later. Calling PyUnicode_AsWideCharString() twice on the same string avoids also the need of encoding the string twice because the result is cached.

I proposed to add a new function using wchar_*t and storing the result in the Unicode string, but the idea was rejected. I don't remember why.

Could you please clarify what you actually intend to do ? Which
function do you want to remove and why ?

The title and description of this ticket don't match :-)

I fail to see the issue. Even though the function is born-deprecated, there are valid use cases for it, even for new code (see http://www.python.org/dev/peps/pep-0393/#deprecations-removals-and-incompatibilities).

Closing the issue as invalid.