Update `bytearray` to contain a `bytes` and provide a zero-copy path to
"extract" the `bytes`. This allows making several code paths more efficient.
This does not move any codepaths to make use of this new API. The documentation
changes include common code patterns which can be made more efficient with
this API.
---
When just changing `bytearray` to contain `bytes` I ran pyperformance on a
`--with-lto --enable-optimizations --with-static-libpython` build and don't see
any major speedups or slowdowns with this; all seems to be in the noise of
my machine (Generally changes under 5% or benchmarks that don't touch
bytes/bytearray).
Co-authored-by: Victor Stinner <vstinner@python.org>
Co-authored-by: Maurycy Pawłowski-Wieroński <5383+maurycy@users.noreply.github.com>
Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Co-authored-by: Loïc Simon <loic.pano@gmail.com>
Co-authored-by: pauleveritt <pauleveritt@me.com>
[main] Update stdtypes.rst
- Added explicit mention of `del s[i]` (item deletion by index) to the Mutable Sequence Types section.
- Clarified that this operation removes the item at the specified index from the sequence.
- Addresses issue #134789.
Also move up the explanation of insertion order preservation. Both paragraphs seemed out of place down where they were.
---------
Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
We had the definition of what makes a character "printable" documented in three places, giving two different definitions.
The definition in the comment on `_PyUnicode_IsPrintable` was inverted; correct that.
With that correction, the two definitions turn out to be equivalent -- but to confirm that, you have to go look up, or happen to know, that those are the only five "Other" categories and only three "Separator" categories in the Unicode character database. That makes it hard for the reader to tell whether they really are the same, or if there's some subtle difference in the intended semantics.
Fix that by cutting the C API docs' and the C comment's copies of the subtle details, in favor of referring to the Python-level docs. That ensures it's explicit that these are all meant to agree, and also lets us concentrate improvements to the wording in one place.
Speaking of which, borrow some ideas from the C comment, along with other tweaks, to hopefully add a bit more clarity to that one newly-centralized copy in the docs.
Also add a thorough test that the implementation agrees with this definition.
Author: Greg Price <gnprice@gmail.com>
Co-authored-by: Greg Price <gnprice@gmail.com>
"Generally, mixed-mode arithmetic combining real and complex variables should
be performed directly, not by first coercing the real to complex, lest the sign
of zero be rendered uninformative; the same goes for combinations of pure
imaginary quantities with complex variables." (c) Kahan, W: Branch cuts for
complex elementary functions.
This patch implements mixed-mode arithmetic rules, combining real and
complex variables as specified by C standards since C99 (in particular,
there is no special version for the true division with real lhs
operand). Most C compilers implementing C99+ Annex G have only these
special rules (without support for imaginary type, which is going to be
deprecated in C2y).
