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PEP 683: Fix some typos (#2348)

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@ -34,7 +34,7 @@ for an immortal object will be considered immutable.
This approach has some possible negative impact, which is explained This approach has some possible negative impact, which is explained
below, along with mitigations. A critical requirement for this change below, along with mitigations. A critical requirement for this change
is that the performance regression be no more than 2-3%. Anything worse is that the performance regression be no more than 2-3%. Anything worse
the performance-neutral requires that the other benefits are proportionally than performance-neutral requires that the other benefits are proportionally
large. Aside from specific applications, the fundamental improvement large. Aside from specific applications, the fundamental improvement
here is that now an object can be truly immutable. here is that now an object can be truly immutable.
@ -111,11 +111,11 @@ This can result in a large performance improvement, especially
memory usage. Several enterprise Python users (e.g. Instagram, memory usage. Several enterprise Python users (e.g. Instagram,
YouTube) have taken advantage of this. However, the above YouTube) have taken advantage of this. However, the above
refcount semantics drastically reduce the benefits and refcount semantics drastically reduce the benefits and
has led to some sub-optimal workarounds. have led to some sub-optimal workarounds.
Also note that "fork" isn't the only operating system mechanism Also note that "fork" isn't the only operating system mechanism
that uses copy-on-write semantics. Anything that uses ``mmap`` that uses copy-on-write semantics. Anything that uses ``mmap``
relies on copy-on-write, including sharing data from shared objects relies on copy-on-write, including sharing data from shared object
files between processes. files between processes.
@ -350,7 +350,7 @@ Scope of Changes
---------------- ----------------
Object immortality is not meant to be a public feature but rather an Object immortality is not meant to be a public feature but rather an
internal one. So the proposal does *not* including adding any new internal one. So the proposal does *not* include adding any new
public C-API, nor any Python API. However, this does not prevent public C-API, nor any Python API. However, this does not prevent
us from adding (publicly accessible) private API to do things us from adding (publicly accessible) private API to do things
like immortalize an object or tell if one is immortal. like immortalize an object or tell if one is immortal.
@ -483,8 +483,8 @@ will be made immortal. That includes the following:
small ints) small ints)
All such objects will be immutable. In the case of the static types, All such objects will be immutable. In the case of the static types,
they will be effectively immutable. ``PyTypeObject`` has some mutable they will only be effectively immutable. ``PyTypeObject`` has some mutable
start (``tp_dict`` and ``tp_subclasses``), but we can work around this state (``tp_dict`` and ``tp_subclasses``), but we can work around this
by storing that state on ``PyInterpreterState`` instead of on the by storing that state on ``PyInterpreterState`` instead of on the
respective static type object. Then the ``__dict__``, etc. getter respective static type object. Then the ``__dict__``, etc. getter
will do a lookup on the current interpreter, if appropriate, instead will do a lookup on the current interpreter, if appropriate, instead
@ -520,7 +520,7 @@ to the runtime state for a small number of objects.
Performance Regression Mitigation Performance Regression Mitigation
--------------------------------- ---------------------------------
In the interest of clarify, here are some of the ways we are going In the interest of clarity, here are some of the ways we are going
to try to recover some of the lost `performance <Performance_>`_: to try to recover some of the lost `performance <Performance_>`_:
* at the end of runtime init, mark all objects as immortal * at the end of runtime init, mark all objects as immortal
@ -594,7 +594,7 @@ Open Issues
References References
========== ==========
.. _Pyston: https://mail.python.org/archives/list/python-dev@python.org/message/TPLEYDCXFQ4AMTW6F6OQFINSIFYBRFCR/ .. _Pyston: https://mail.python.org/archives/list/python-dev@python.org/message/JLHRTBJGKAENPNZURV4CIJSO6HI62BV3/
Prior Art Prior Art
--------- ---------