PEP 642: Fix footnotes (#2718)
This commit is contained in:
parent
5e0be8f86f
commit
3a792e4a1d
37
pep-0642.rst
37
pep-0642.rst
|
@ -106,7 +106,7 @@ turn it into a general purpose wildcard marker that always skips making a new
|
|||
local variable binding.
|
||||
|
||||
While it has not yet been put forward as a PEP, Mark Shannon has a pre-PEP draft
|
||||
[8_] expressing several concerns about the runtime semantics of the pattern
|
||||
[8]_ expressing several concerns about the runtime semantics of the pattern
|
||||
matching proposal in :pep:`634`. This PEP is somewhat complementary to that one, as
|
||||
even though this PEP is mostly about surface syntax changes rather than major
|
||||
semantic changes, it does propose that the Abstract Syntax Tree definition be
|
||||
|
@ -127,7 +127,7 @@ neither ordinary expressions *nor* the existing assignment target syntax provide
|
|||
an adequate foundation for the syntax used in match patterns.
|
||||
|
||||
While the PEP didn't explicitly state this assumption, one of the PEP authors
|
||||
explained it clearly on python-dev [1_]:
|
||||
explained it clearly on python-dev [1]_:
|
||||
|
||||
The actual problem that I see is that we have different cultures/intuitions
|
||||
fundamentally clashing here. In particular, so many programmers welcome
|
||||
|
@ -155,7 +155,7 @@ The first iteration of this PEP was then born out of an attempt to show that the
|
|||
second assertion was not accurate, and that match patterns could be treated
|
||||
as a variation on assignment targets without leading to inherent contradictions.
|
||||
(An earlier PR submitted to list this option in the "Rejected Ideas" section
|
||||
of the original :pep:`622` had previously been declined [2_]).
|
||||
of the original :pep:`622` had previously been declined [2]_).
|
||||
|
||||
However, the review process for this PEP strongly suggested that not only did
|
||||
the contradictions that Tobias mentioned in his email exist, but they were also
|
||||
|
@ -164,7 +164,7 @@ Accordingly, this PEP was changed to go even further than :pep:`634`, and largel
|
|||
abandon alignment between the sequence matching syntax and the existing iterable
|
||||
unpacking syntax (effectively answering "Not really, as least as far as the
|
||||
exact syntax is concerned" to the first question raised in the DLS'20 paper
|
||||
[9_]: "Can we extend a feature like iterable unpacking to work for more general
|
||||
[9]_: "Can we extend a feature like iterable unpacking to work for more general
|
||||
object and data layouts?").
|
||||
|
||||
This resulted in a complete reversal of the goals of the PEP: rather than
|
||||
|
@ -1091,7 +1091,7 @@ next question is to ask exactly what that prefix should be.
|
|||
The initially published version of this PEP proposed using the previously
|
||||
unused ``?`` symbol as the prefix for equality constraints, and ``?is`` as the
|
||||
prefix for identity constraints. When reviewing the PEP, Steven D'Aprano
|
||||
presented a compelling counterproposal [5_] to use the existing comparison
|
||||
presented a compelling counterproposal [5]_ to use the existing comparison
|
||||
operators (``==`` and ``is``) instead.
|
||||
|
||||
There were a few concerns with ``==`` as a prefix that kept it from being
|
||||
|
@ -1142,14 +1142,14 @@ marker would be a bad idea. With the syntax for value constraints changed
|
|||
to use existing comparison operations rather than ``?`` and ``?is``, that
|
||||
argument holds for this PEP as well.
|
||||
|
||||
However, as noted by Thomas Wouters in [6_], :pep:`634`'s choice of ``_`` remains
|
||||
However, as noted by Thomas Wouters in [6]_, :pep:`634`'s choice of ``_`` remains
|
||||
problematic as it would likely mean that match patterns would have a *permanent*
|
||||
difference from all other parts of Python - the use of ``_`` in software
|
||||
internationalisation and at the interactive prompt means that there isn't really
|
||||
a plausible path towards using it as a general purpose "skipped binding" marker.
|
||||
|
||||
``__`` is an alternative "this value is not needed" marker drawn from a Stack
|
||||
Overflow answer [7_] (originally posted by the author of this PEP) on the
|
||||
Overflow answer [7]_ (originally posted by the author of this PEP) on the
|
||||
various meanings of ``_`` in existing Python code.
|
||||
|
||||
This PEP also proposes adopting an implementation technique that limits
|
||||
|
@ -1764,8 +1764,8 @@ a human reader as well: ``case {0: == 0}:``
|
|||
Reference Implementation
|
||||
========================
|
||||
|
||||
A draft reference implementation for this PEP [3_] has been derived from Brandt
|
||||
Bucher's reference implementation for :pep:`634` [4_].
|
||||
A draft reference implementation for this PEP [3]_ has been derived from Brandt
|
||||
Bucher's reference implementation for :pep:`634` [4]_.
|
||||
|
||||
Relative to the text of this PEP, the draft reference implementation has not
|
||||
yet complemented the special casing of several builtin and standard library
|
||||
|
@ -1860,7 +1860,7 @@ References
|
|||
https://gvanrossum.github.io/docs/PyPatternMatching.pdf
|
||||
|
||||
|
||||
.. _Appendix A:
|
||||
.. _642-appendix-a:
|
||||
|
||||
Appendix A -- Full Grammar
|
||||
==========================
|
||||
|
@ -1970,7 +1970,7 @@ Notation used beyond standard EBNF is as per :pep:`534`:
|
|||
| '**' '{' [attrs_constraint_elements] '}'
|
||||
|
||||
|
||||
.. _Appendix B:
|
||||
.. _642-appendix-b:
|
||||
|
||||
Appendix B: Summary of Abstract Syntax Tree changes
|
||||
===================================================
|
||||
|
@ -2003,7 +2003,7 @@ The following new nodes are added to the AST by this PEP::
|
|||
matchop = EqCheck | IdCheck
|
||||
|
||||
|
||||
.. _Appendix C:
|
||||
.. _642-appendix-c:
|
||||
|
||||
Appendix C: Summary of changes relative to PEP 634
|
||||
==================================================
|
||||
|
@ -2073,7 +2073,7 @@ binary addition and subtraction operations on constants, so proposals like
|
|||
:pep:`634` have to do work in later compilation steps to check for correct usage.
|
||||
|
||||
|
||||
.. _Appendix D:
|
||||
.. _642-appendix-d:
|
||||
|
||||
Appendix D: History of changes to this proposal
|
||||
===============================================
|
||||
|
@ -2104,14 +2104,3 @@ Copyright
|
|||
|
||||
This document is placed in the public domain or under the
|
||||
CC0-1.0-Universal license, whichever is more permissive.
|
||||
|
||||
|
||||
|
||||
..
|
||||
Local Variables:
|
||||
mode: indented-text
|
||||
indent-tabs-mode: nil
|
||||
sentence-end-double-space: t
|
||||
fill-column: 70
|
||||
coding: utf-8
|
||||
End:
|
||||
|
|
Loading…
Reference in New Issue