New submission from STINNER Victor <vstin...@python.org>: Python has the concept of "immortal" interned strings: PyUnicode_InternImmortal().
The feature was first introduced in the Python 2 "str" (bytes) type, bpo-576101 (commit 45ec02aed14685c353e55841b5acbc0dadee76f8). New PyString_InternImmortal() function. commit 45ec02aed14685c353e55841b5acbc0dadee76f8 Author: Guido van Rossum <gu...@python.org> Date: Mon Aug 19 21:43:18 2002 +0000 SF patch 576101, by Oren Tirosh: alternative implementation of interning. I modified Oren's patch significantly, but the basic idea and most of the implementation is unchanged. Interned strings created with PyString_InternInPlace() are now mortal, and you must keep a reference to the resulting string around; use the new function PyString_InternImmortal() to create immortal interned strings. Later, the feature was added to the PyUnicodeObject type, new PyUnicode_InternImmortal() function: commit 1680713e524016d93a94114c4a874ad71a090b95 Author: Walter Dörwald <wal...@livinglogic.de> Date: Fri May 25 13:52:07 2007 +0000 Add interning of unicode strings by copying the functionality from stringobject.c. Intern "True" and "False" in bool_repr() again as it was in the 8bit string era. Since Python 3.10, (mortal) interned strings are cleared at Python exit in Py_Finalize(). It avoids leaking memory when Python is embedded in an application: bpo-1635741. commit 666ecfb0957a2fa0df5e2bd03804195de74bdfbf Author: Victor Stinner <vstin...@python.org> Date: Thu Jul 2 01:19:57 2020 +0200 bpo-1635741: Release Unicode interned strings at exit (GH-21269) * PyUnicode_InternInPlace() now ensures that interned strings are ready. * Add _PyUnicode_ClearInterned(). * Py_Finalize() now releases Unicode interned strings: call _PyUnicode_ClearInterned(). -- PyUnicode_InternImmortal() is not used in the Python standard library. I propose to start deprecating the function and remove it in Python 3.12 (PEP 387 requires a deprecation for 2 releases). In Python 3.10, calling the function will emit a DeprecationWarning at runtime. Note: PyString_InternImmortal() (for bytes strings) has been removed from Python 3.0. ---------- components: Interpreter Core messages: 376237 nosy: inada.naoki, serhiy.storchaka, vstinner priority: normal severity: normal status: open title: Deprecate immortal interned strings: PyUnicode_InternImmortal() versions: Python 3.10 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue41692> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com