Deploy preview for PR 1199 🛫

Author: josix

pr-preview/pr-1199/_sources/c-api/intro.rst.txt

@@ -127,6 +127,35 @@ complete listing.
 
    .. versionadded:: 3.3
 
+.. c:macro:: Py_ALIGNED(num)
+
+   Specify alignment to *num* bytes on compilers that support it.
+
+   Consider using the C11 standard ``_Alignas`` specifier over this macro.
+
+.. c:macro:: Py_ARITHMETIC_RIGHT_SHIFT(type, integer, positions)
+
+   Similar to ``integer >> positions``, but forces sign extension, as the C
+   standard does not define whether a right-shift of a signed integer will
+   perform sign extension or a zero-fill.
+
+   *integer* should be any signed integer type.
+   *positions* is the number of positions to shift to the right.
+
+   Both *integer* and *positions* can be evaluated more than once;
+   consequently, avoid directly passing a function call or some other
+   operation with side-effects to this macro. Instead, store the result as a
+   variable and then pass it.
+
+   *type* is unused and only kept for backwards compatibility. Historically,
+   *type* was used to cast *integer*.
+
+   .. versionchanged:: 3.1
+
+      This macro is now valid for all signed integer types, not just those for
+      which ``unsigned type`` is legal. As a result, *type* is no longer
+      used.
+
 .. c:macro:: Py_ALWAYS_INLINE
 
    Ask the compiler to always inline a static inline function. The compiler can
@@ -149,6 +178,15 @@ complete listing.
 
    .. versionadded:: 3.11
 
+.. c:macro:: Py_CAN_START_THREADS
+
+   If this macro is defined, then the current system is able to start threads.
+
+   Currently, all systems supported by CPython (per :pep:`11`), with the
+   exception of some WebAssembly platforms, support starting threads.
+
+   .. versionadded:: 3.13
+
 .. c:macro:: Py_CHARMASK(c)
 
    Argument must be a character or an integer in the range [-128, 127] or [0,
@@ -166,11 +204,35 @@ complete listing.
    .. versionchanged:: 3.8
       MSVC support was added.
 
+.. c:macro:: Py_FORCE_EXPANSION(X)
+
+   This is equivalent to ``X``, which is useful for token-pasting in
+   macros, as macro expansions in *X* are forcefully evaluated by the
+   preprocessor.
+
+.. c:macro:: Py_GCC_ATTRIBUTE(name)
+
+   Use a GCC attribute *name*, hiding it from compilers that don't support GCC
+   attributes (such as MSVC).
+
+   This expands to ``__attribute__((name))`` on a GCC compiler, and expands
+   to nothing on compilers that don't support GCC attributes.
+
 .. c:macro:: Py_GETENV(s)
 
    Like ``getenv(s)``, but returns ``NULL`` if :option:`-E` was passed on the
    command line (see :c:member:`PyConfig.use_environment`).
 
+.. c:macro:: Py_LL(number)
+
+   Use *number* as a ``long long`` integer literal.
+
+   This usally expands to *number* followed by ``LL``, but will expand to some
+   compiler-specific suffixes (such as ``I64``) on older compilers.
+
+   In modern versions of Python, this macro is not very useful, as C99 and
+   later require the ``LL`` suffix to be valid for an integer.
+
 .. c:macro:: Py_LOCAL(type)
 
    Declare a function returning the specified *type* using a fast-calling
@@ -228,13 +290,37 @@ complete listing.
 
    .. versionadded:: 3.11
 
+.. c:macro:: Py_SAFE_DOWNCAST(value, larger, smaller)
+
+   Cast *value* to type *smaller* from type *larger*, validating that no
+   information was lost.
+
+   On release builds of Python, this is roughly equivalent to
+   ``(smaller) value`` (in C++, ``static_cast<smaller>(value)`` will be
+   used instead).
+
+   On debug builds (implying that :c:macro:`Py_DEBUG` is defined), this asserts
+   that no information was lost with the cast from *larger* to *smaller*.
+
+   *value*, *larger*, and *smaller* may all be evaluated more than once in the
+   expression; consequently, do not pass an expression with side-effects directly to
+   this macro.
+
 .. c:macro:: Py_STRINGIFY(x)
 
    Convert ``x`` to a C string.  E.g. ``Py_STRINGIFY(123)`` returns
    ``"123"``.
 
    .. versionadded:: 3.4
 
+.. c:macro:: Py_ULL(number)
+
+   Similar to :c:macro:`Py_LL`, but *number* will be an ``unsigned long long``
+   literal instead. This is done by appending ``U`` to the result of ``Py_LL``.
+
+   In modern versions of Python, this macro is not very useful, as C99 and
+   later require the ``ULL``/``LLU`` suffixes to be valid for an integer.
+
 .. c:macro:: Py_UNREACHABLE()
 
    Use this when you have a code path that cannot be reached by design.
@@ -375,6 +461,16 @@ complete listing.
    This macro is intended for defining CPython's C API itself;
    extension modules should not use it for their own symbols.
 
+.. c:macro:: Py_VA_COPY
+
+   This is a :term:`soft deprecated` alias to the C99-standard ``va_copy``
+   function.
+
+   Historically, this would use a compiler-specific method to copy a ``va_list``.
+
+   .. versionchanged:: 3.6
+      This is now an alias to ``va_copy``.
+
 
 .. _api-objects:
 

pr-preview/pr-1199/_sources/library/itertools.rst.txt

@@ -845,7 +845,8 @@ and :term:`generators <generator>` which incur interpreter overhead.
    from contextlib import suppress
    from functools import reduce
    from math import comb, isqrt, prod, sumprod
-   from operator import getitem, is_not, itemgetter, mul, neg
+   from operator import getitem, is_not, itemgetter, mul, neg, truediv
+
 
    # ==== Basic one liners ====
 
@@ -858,9 +859,10 @@ and :term:`generators <generator>` which incur interpreter overhead.
        # prepend(1, [2, 3, 4]) → 1 2 3 4
        return chain([value], iterable)
 
-   def tabulate(function, start=0):
-       "Return function(0), function(1), ..."
-       return map(function, count(start))
+   def running_mean(iterable):
+       "Yield the average of all values seen so far."
+       # running_mean([8.5, 9.5, 7.5, 6.5]) -> 8.5 9.0 8.5 8.0
+       return map(truediv, accumulate(iterable), count(1))
 
    def repeatfunc(function, times=None, *args):
        "Repeat calls to a function with specified arguments."
@@ -913,6 +915,7 @@ and :term:`generators <generator>` which incur interpreter overhead.
        # all_equal('4٤௪౪໔', key=int) → True
        return len(take(2, groupby(iterable, key))) <= 1
 
+
    # ==== Data pipelines ====
 
    def unique_justseen(iterable, key=None):
@@ -1021,6 +1024,7 @@ and :term:`generators <generator>` which incur interpreter overhead.
            while True:
                yield function()
 
+
    # ==== Mathematical operations ====
 
    def multinomial(*counts):
@@ -1040,6 +1044,7 @@ and :term:`generators <generator>` which incur interpreter overhead.
        # sum_of_squares([10, 20, 30]) → 1400
        return sumprod(*tee(iterable))
 
+
    # ==== Matrix operations ====
 
    def reshape(matrix, columns):
@@ -1058,6 +1063,7 @@ and :term:`generators <generator>` which incur interpreter overhead.
        n = len(m2[0])
        return batched(starmap(sumprod, product(m1, transpose(m2))), n)
 
+
    # ==== Polynomial arithmetic ====
 
    def convolve(signal, kernel):
@@ -1114,6 +1120,7 @@ and :term:`generators <generator>` which incur interpreter overhead.
        powers = reversed(range(1, n))
        return list(map(mul, coefficients, powers))
 
+
    # ==== Number theory ====
 
    def sieve(n):
@@ -1230,8 +1237,8 @@ and :term:`generators <generator>` which incur interpreter overhead.
     [(0, 'a'), (1, 'b'), (2, 'c')]
 
 
-    >>> list(islice(tabulate(lambda x: 2*x), 4))
-    [0, 2, 4, 6]
+    >>> list(running_mean([8.5, 9.5, 7.5, 6.5]))
+    [8.5, 9.0, 8.5, 8.0]
 
 
     >>> for _ in loops(5):
@@ -1798,6 +1805,10 @@ and :term:`generators <generator>` which incur interpreter overhead.
 
     # Old recipes and their tests which are guaranteed to continue to work.
 
+    def tabulate(function, start=0):
+        "Return function(0), function(1), ..."
+        return map(function, count(start))
+
     def old_sumprod_recipe(vec1, vec2):
         "Compute a sum of products."
         return sum(starmap(operator.mul, zip(vec1, vec2, strict=True)))
@@ -1877,6 +1888,10 @@ and :term:`generators <generator>` which incur interpreter overhead.
 .. doctest::
     :hide:
 
+    >>> list(islice(tabulate(lambda x: 2*x), 4))
+    [0, 2, 4, 6]
+
+
     >>> dotproduct([1,2,3], [4,5,6])
     32
 

pr-preview/pr-1199/_sources/library/stdtypes.rst.txt

@@ -2751,6 +2751,19 @@ expression support in the :mod:`re` module).
    test string beginning at that position.  With optional *end*, stop comparing
    string at that position.
 
+   For example:
+
+   .. doctest::
+
+      >>> 'Python'.startswith('Py')
+      True
+      >>> 'a tuple of prefixes'.startswith(('at', 'a'))
+      True
+      >>> 'Python is amazing'.startswith('is', 7)
+      True
+
+   See also :meth:`endswith` and :meth:`removeprefix`.
+
 
 .. method:: str.strip(chars=None, /)
 

pr-preview/pr-1199/about.html

@@ -326,7 +326,7 @@ <h3>導航</h3>
 <a href="https://www.python.org/psf/donations/">敬請捐贈。</a>
 <br>
     <br>
-      最後更新於 2月 04, 2026 (15:57 UTC)。
+      最後更新於 2月 05, 2026 (07:17 UTC)。
 
       <a href="/bugs.html">發現 bug</a>？
 

pr-preview/pr-1199/bugs.html

@@ -235,7 +235,7 @@ <h2>說明文件的錯誤<a class="headerlink" href="#documentation-bugs" title=
 </section>
 <section id="getting-started-contributing-to-python-yourself">
 <span id="contributing-to-python"></span><h2>開始讓自己貢獻 Python<a class="headerlink" href="#getting-started-contributing-to-python-yourself" title="連結到這個標頭">¶</a></h2>
-<p>除了只是回報你所發現的錯誤之外，同樣也歡迎你提交修正它們的修補程式 (patch)。你可以在 <a class="reference external" href="https://mail.python.org/mailman3/lists/core-mentorship.python.org/">Python 開發者指南</a>中找到如何開始修補 Python 的更多資訊。如果你有任何問題，<a class="reference external" href="https://devguide.python.org/">核心導師郵寄清單</a>是一個友善的地方，你可以在那裡得到，關於 Python 修正錯誤的過程中，所有問題的答案。</p>
+<p>除了只是回報你所發現的錯誤之外，同樣也歡迎你提交修正它們的修補程式 (patch)。你可以在 <a class="reference external" href="https://devguide.python.org/">Python 開發者指南</a>中找到如何開始修補 Python 的更多資訊。如果你有任何問題，<a class="reference external" href="https://mail.python.org/mailman3/lists/core-mentorship.python.org/">核心導師郵寄清單</a>是一個友善的地方，你可以在那裡得到，關於 Python 修正錯誤的過程中，所有問題的答案。</p>
 </section>
 </section>
 
@@ -363,7 +363,7 @@ <h3>導航</h3>
 <a href="https://www.python.org/psf/donations/">敬請捐贈。</a>
 <br>
     <br>
-      最後更新於 2月 04, 2026 (15:57 UTC)。
+      最後更新於 2月 05, 2026 (07:17 UTC)。
 
       <a href="/bugs.html">發現 bug</a>？
 

pr-preview/pr-1199/c-api/abstract.html

@@ -335,7 +335,7 @@ <h3>導航</h3>
 <a href="https://www.python.org/psf/donations/">敬請捐贈。</a>
 <br>
     <br>
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+      最後更新於 2月 05, 2026 (07:17 UTC)。
 
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pr-preview/pr-1199/c-api/allocation.html

@@ -544,7 +544,7 @@ <h3>導航</h3>
 <a href="https://www.python.org/psf/donations/">敬請捐贈。</a>
 <br>
     <br>
-      最後更新於 2月 04, 2026 (15:57 UTC)。
+      最後更新於 2月 05, 2026 (07:17 UTC)。
 
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pr-preview/pr-1199/c-api/apiabiversion.html

@@ -484,7 +484,7 @@ <h3>導航</h3>
 <a href="https://www.python.org/psf/donations/">敬請捐贈。</a>
 <br>
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+      最後更新於 2月 05, 2026 (07:17 UTC)。
 
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pr-preview/pr-1199/c-api/arg.html

@@ -966,7 +966,7 @@ <h3>導航</h3>
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 <br>
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+      最後更新於 2月 05, 2026 (07:17 UTC)。
 
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pr-preview/pr-1199/c-api/bool.html

@@ -346,7 +346,7 @@ <h3>導航</h3>
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 <br>
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+      最後更新於 2月 05, 2026 (07:17 UTC)。
 
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